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TCz
04-08-2012, 03:18 PM
I didn't want to divert the other AR thread, but I am curious. I also ran a search, and it appears that this has never been explicitly discussed here.

Does the mid length offer real, significant, and quantifiable benefits over the carbine length in terms of durability, longevity, and usability?
I'd like to hear from the SME's, but if anyone else has input, I'd appreciate that too.
Sight radius is obvious, so I think we can skip that one.

Jay Cunningham
04-08-2012, 03:31 PM
I'm not an SME, but I'm pretty familiar with the topic.

Look, the honest answer to your question is "no".

I say that because there are mountains of real data on 20" rifle systems, 14.5" and 16" carbine systems, and 10.3" carbine systems. This is all real-world data. There is not much info about mid-length systems outside of training schools and private company testing.

I am not saying that there's anything wrong with a mid-length AR. I have one. But there isn't anything so awesome about them that they blow something else out of the water.

Longer iron sight radius? Yes, that's true. Longer 9" handguard? Yes, that's true. Softer felt recoil? True on paper but highly subjective. Operation at lower pressure thereby less "wear and tear" on the gun? True on paper but where is the mountain of actual hard data to compare? It doesn't exist.

I think 16" middy ARs are just dandy. I do think that 14.5" middys are starting to push it reliability-wise, especially when you factor in Obsessive Buffer Tweaking Syndrome.

orionz06
04-08-2012, 03:32 PM
A mid length AR runs at a lower pressure and will have a slightly different recoil impulse, one that some prefer. It is also alluded to that there will be less "stress" on part and some parts will last longer. I am unaware of any testing performed at any volume to prove this to be correct.

What we do know is that if you buy a Daniel Defense or BCM mid length gun you will get a good gun. If you get a 16" or longer gun the mid length should have zero issues and might feel a little better when shooting.

When someone who is buying brand new asks which $1000 gun to go with, BCM carbine or BCM mid length I always say mid length. If you have a carbine gun just shoot it and forget all about the minutia that makes very little difference when you actually get to the range.

Odin Bravo One
04-08-2012, 06:16 PM
I personally stick with the guns with proven track records over the long haul.

Buy whatever suits your fancy.

rob_s
04-08-2012, 06:16 PM
Pretty much exactly what Jay said.

TCz
04-08-2012, 08:50 PM
I'm not an SME, but I'm pretty familiar with the topic.

Look, the honest answer to your question is "no".

I say that because there are mountains of real data on 20" rifle systems, 14.5" and 16" carbine systems, and 10.3" carbine systems. This is all real-world data. There is not much info about mid-length systems outside of training schools and private company testing.

I am not saying that there's anything wrong with a mid-length AR. I have one. But there isn't anything so awesome about them that they blow something else out of the water.

Longer iron sight radius? Yes, that's true. Longer 9" handguard? Yes, that's true. Softer felt recoil? True on paper but highly subjective. Operation at lower pressure thereby less "wear and tear" on the gun? True on paper but where is the mountain of actual hard data to compare? It doesn't exist.

I think 16" middy ARs are just dandy. I do think that 14.5" middys are starting to push it reliability-wise, especially when you factor in Obsessive Buffer Tweaking Syndrome.


So, to recap, mids offer real and possibly significant advantages on paper, but these advantages can't be quantified due to the lack of hard data to demonstrate them, meaning they could very well be negligible, and I should quit worrying about it.

I think that's what I needed to know.

fuse
04-09-2012, 12:40 AM
To me the mid length is sort of the obvious next step in the evolution of the carbine.

Doesn't the HK IAR use a mid length system? Albeit with a gas piston. Or would the proprietary piston system make a comparison invalid?

I predict that if Colt started making a mid length gun, everyone who currently sack rides the 6920 would recommend the new mid length colt over the current carbine version. You know it's true. The many advantages are undeniable. The only disadvantage mentioned is lack of a huge track record, outside some training schools. OK, fine.

Would we recommend a midlength BCM or DD if we honestly thought they would be less reliable than their carbine brethren?

rob_s
04-09-2012, 05:20 AM
So, to recap, mids offer real and possibly significant advantages on paper, but these advantages can't be quantified due to the lack of hard data to demonstrate them, meaning they could very well be negligible, and I should quit worrying about it.

I think that's what I needed to know.

"real and significant" may be over-stating it IMO but essentially, yes.

rob_s
04-09-2012, 05:27 AM
To me the mid length is sort of the obvious next step in the evolution of the carbine.

Doesn't the HK IAR use a mid length system? Albeit with a gas piston. Or would the proprietary piston system make a comparison invalid?

I predict that if Colt started making a mid length gun, everyone who currently sack rides the 6920 would recommend the new mid length colt over the current carbine version. You know it's true. The many advantages are undeniable. The only disadvantage mentioned is lack of a huge track record, outside some training schools. OK, fine.

Would we recommend a midlength BCM or DD if we honestly thought they would be less reliable than their carbine brethren?

emotional outbursts like "sack ride" and overly-aggressive (and mistaken, incidentally) statements like "you know it's true" and "advantages are undeniable" belie a lack of confidence in your own position.

Provide quantifiable data to back up your claims that the mid-length is "better", and define what "better" means in this case. Otherwise, no matter how much you don't like the fact, it's conjecture (or, I suspect in this case, repeating of conjecture) and theory at best.

I don't think anyone is saying "don't buy a mid-length".

To be clear, I have nothing against the mid-length, don't "sack ride" anything, but also don't "sack ride" the theory and conjecture that the mid-length is better in any facet other than increased sight radius and extended handguards and may, in fact, offer potential (and theoretical) downsides.

Little Creek
04-09-2012, 06:30 AM
I bought my first AR-15 style carbine roughly six months ago. It has a front sight tower. I put a magpul handguard on it. I have been thinking I would like the midlength hand guard better because it would give me more "rail estate" therefore more flexibility in terms of supporting hand position etc. That being said, I may buy another AR-15 (one is none and two is one). I have learned some things I like and do not like since I bought my first carbine. I think I would like a floating handguard with a folding backup front sight in lieu of a carbine length gas system with a front sight tower.

What do you guys think?

orionz06
04-09-2012, 06:42 AM
The only disadvantage mentioned is lack of a huge track record, outside some training schools.

Is there somewhere that has a huge track record with mid length guns that everyone is missing?

Jay Cunningham
04-09-2012, 06:49 AM
Lower operating pressures can result in "softer" extraction. Robust extraction could be a good trait in a fighting gun. Combine that with Obsessive Buffer Tweaking Syndrome (and especially 14.5" barrels) and you're getting closer to potential short stroke territory.

There is also no "standard" for the middy system.

orionz06
04-09-2012, 06:51 AM
14.5" mid length guns are really the only ones I have ever seen start to spit, sputter, and choke when made from known good companies like BCM.

Little Creek
04-09-2012, 07:06 AM
I want a longer handguard without a front sight constantly in my sight picture. I think I want the folding front sight more than I want a longer hand guard. It appears that I should stay with a carbine length gas system. Is it a good idea to "shave" the front sight tower off and install a longer "floating" handguard that will support a folding front sight. Is it better to replace thr front sight tower with a low profile gas block in order to get a longer floating handquard. Of course, a railed gas block would support a folding front sight. What do you guys recommend? Bear in mind, I want a reliabile carbine. I will probably not put more than 1,500 rounds a year through it.

Thanks in advance for your input and advice.

rob_s
04-09-2012, 07:35 AM
Let me say something before this gets all...well...

I'm not against the mid-length. I'm not arguing against the mid-length. I'm not saying the mid-length doesn't result in reduced pressure (although just to be clear, if you're going to make that claim you ought to link to the data that supports it). What I AM saying is that I'd like to see data on the tangible benefits of this reduced pressure (provided someone can provide the support for that claim) as relates to claims of reduced "felt recoil" and reduced "parts wear", especially as pertains to a properly configured carbine-length system. and if we're going to discuss recoil, the guns need to also weigh the same and have the same center of gravity.

GJM
04-09-2012, 07:55 AM
So, Rob, it someone offered you for free, a Colt 6920 upper or a BCM 16 inch, mid-length gas system upper, which would you take?

rob_s
04-09-2012, 08:12 AM
So, Rob, it someone offered you for free, a Colt 6920 upper or a BCM 16 inch, mid-length gas system upper, which would you take?

I need more details. :p

When you say "upper" are you talking about everything that resides in, and comes attached to, the upper receiver on a complete gun with the exception of the parts attached via the takedown and pivot pins? and including stock, plastic, handguards?

and, what barrel profile on the BCM, and can I change the 6920 upper to a 6720?

To answer my own questions, if you were giving me everything not attached to the two pins, and both barrels were lightweight, I'd take the Colt.

Which is NO slam on BCM. They are an awesome company, owned by the best guy I know in the industry, and they make a GREAT product.

GJM
04-09-2012, 08:32 AM
Lately, I have been partial to a BCM 16, mid-length, skinny barrel upper, with the LW VTAC hand guard, because they shoot well for me, and have been lightweight to carry in the field. Wondered if I have been missing something with the 6720?

fuse
04-09-2012, 08:48 AM
Lower operating pressures can result in "softer" extraction. Robust extraction could be a good trait in a fighting gun. Combine that with Obsessive Buffer Tweaking Syndrome (and especially 14.5" barrels) and you're getting closer to potential short stroke territory.

There is also no "standard" for the middy system.

Doesn't the rifle length system have the lowest pressure/softest recoil of all 3? No one has ever said a rifle length AR is not a reliable fighting gun.

Jay Cunningham
04-09-2012, 09:09 AM
Well, if you have some numbers, post them up.

The 20" rifle is a combat-proven system with 40 some years of refinement. There is a Technical Data Package for the system - a known spec for everything.

We know how it works, why it works, what breaks and when. There is a mountain of hard data bigger than Everest.

LOKNLOD
04-09-2012, 10:16 AM
The rifle gas system is also usually used with a rifle buffer system, which is a bit different animal, plus a little less commonly f'd with by the OBTS crowd Jay mentioned earlier. If you start screwing with the buffer on a rifle system it can have problems too.

jmjames
04-09-2012, 11:31 AM
Since there is so much experience with the rifle length systems, does anyone have data on that systems advantages/disadvantages? One would think that if the gas system truly made a difference in things like parts wear, comparing rifles to carbines would definitely show it, and then you could get an idea if the difference was large enough for a mid-length system to have enough of those differences to be important (ie: if it is a 10% difference between rifle and carbine, mid-length is going to show between 0% and 10% difference and quite likely closer to 3% - 8%, which may not be enough to matter).

J.Ja

LittleLebowski
04-09-2012, 11:51 AM
I used to only plan on or buy middys and then I got my 5.45 carbine. Honestly, I don't care which gas system I use now. I cannot tell a difference except slightly smoother recoil impulse. Handguards abound to give you a better forward grip, extractor upgrades are less than $5, and as already mentioned, there's no quantifiable data on middys versus carbine except for maybe EAG's well known (and laudable) data keeping on malfunctions in their courses.

So, it depends on price to me. Both have served me very well.

SecondsCount
04-09-2012, 12:06 PM
I have two midlength carbines, one is a factory built BCM 16" upper, and the other is an upper that I built based on a 16" Sabre Defense barrel.

All I can say is that they both run great with standard buffers, my reloads, and factory stuff including hotter 5.56 ammo. Neither one likes steel cased ammo which is something to consider if you are going to run the cheap stuff.

Simms65
04-09-2012, 02:12 PM
My main AR is a 16" Mid length, and I've hammered the crap out of it with whatever ammo I can find, an extremely lax cleaning schedule, etc. Right now it is in the range of ~1500 rounds of .223/5.56 and ~2000 rounds of .22lr with a conversion kit since the last cleaning. That's been since sometime in January. IIRC there have been 3 FTE's with Tula ammo in that time period and 0 with any other ammo. I don't count the occasional issue with 22lr (maybe one every 200-300 rounds) just because of the finicky nature of 22's. I'm a fan. Of course I've had 16" carbines, and currently have a 12" carbine. None have caused any significant issues that weren't user driven.

My opinion is 6 or 1/2 dozen. Given a choice for a 16" I'd probably go mid again, but if the price was right I wouldn't cry over a carbine.

Ed L
04-10-2012, 03:19 PM
Lower operating pressures can result in "softer" extraction. Robust extraction could be a good trait in a fighting gun..

Very good points, especially about robust extraction being a good thing in a fighting gun.

I wound up picking up a BCM EAG midlength upper with a 14.5" HF barrel after I saw that I could sell one of my carbine length uppers and some other unused guns/equipment and buy it. Before buying I fired one side-by-side a carbine length upper and concluded that the midlength did indeed have a bit less recoil impulse (but we are talking 5.56mm ammo, so there isn't much of an impulse to begin with).

So far it has a bit over 2k rounds through it, including a Spartan Tactical class and Jason Falla class where the temps were in the teens with me firing .223 ammo without a single issue. I have something like 2.5k rounds through the gun without a single malfunction.

Having said all that, I wouldn't feel terrible if I had to return to using a carbine length gas system. I still have 2 Colt carbine length uppers that are not going anywhere.

I would not have considered the midlength if it were not being manufactured by a quality company like BCm, nor would I if Pat Rogers had not given it his endorsement.


Combine that with Obsessive Buffer Tweaking Syndrome (and especially 14.5" barrels) and you're getting closer to potential short stroke territory.

Obsessive Buffer Tweaking Syndrome? I obviously don't get out enough (or read enough threads), because I have no idea what that is. Before buying the 14.5" EAG BCM midlength I asked Pat if it would run okay with my power which has the H1 buffer.

He said it would.

I put it on that lower with the H1 buffer and it has run perfectly so far.

If I had to start experimenting with springs or buffers to get the thing to run reliably I would have sold it long ago.

I will say this: anyone about to buy their first AR who has enough for a Colt 6920. 6720, or a BCM carbine length but is holding out for a midlength should buy one of the above mentioned carbines right now rather than waiting to save up more for the midlength.

orionz06
04-10-2012, 04:21 PM
Obsessive Buffer Tweaking Syndrome? I obviously don't get out enough (or read enough threads), because I have no diea what that is.

Basically it is people who shouldn't own hand tools messing with crap in their reliable guns making them less reliable in search of something that will not alter their performance in a positive manner. Those people would be best served spending the time watching Glee or doing something else besides screwing up a working gun.

DocGKR
04-10-2012, 04:43 PM
I have generally run Colt rifles with carbine length gas systems like the 6520, 6920, and 6720 for the last 2 decades--these work great. Recently I have begun to use 16" mid-length rifles from quality vendors like MSTN, BCM, Centurian, and LaRue--these also work fantastically. The mid-length gas systems subjectively have less felt recoil and anecdotally appear to offer a longer lifespans based on reports from several dozen in service the past 4 years or so.

Both work as long as they are built correctly.

fuse
04-10-2012, 09:29 PM
Obsessive Buffer Tweaking Syndrome? I obviously don't get out enough (or read enough threads), because I have no diea what that is. Before buying the 14.5" EAG BCM midlength I asked Pat if it would run okay with my power which has the H1 buffer.

He said it would.

I put it on that lower with the H1 buffer and it has run perfectly so far.



This has been my experience as well. I started with an H2 in my 14.5 middy, it worked fine. then I read on the internet that it might not work as well as things become dirty, so I bought an H1. and that also works.

Tamara
04-11-2012, 07:38 AM
Basically it is people who shouldn't own hand tools messing with crap in their reliable guns making them less reliable in search of something that will not alter their performance in a positive manner.

Coworker: "Hey, Tam, have your tried those new Tripp Cobramags yet?"

Me: "No, why would I? My gun's running fine with 47Ds."

Coworker: "But the new Tripp mags are supposed to be the best!"

Me: "What're they gonna do for me? Make my gun even not-jammier?"

JRas
04-15-2012, 09:55 AM
good read
http://www.03designgroup.com/technotes/carbine-vs-mid-length-gas-system

fuse
04-15-2012, 02:13 PM
good read
http://www.03designgroup.com/technotes/carbine-vs-mid-length-gas-system

Yeah, I always thought the whole 7.5 inches thing was the likely genesis of the mid-length.

I reckon without the NFA of 1934 the common 16" barrel and the mid-length system wouldn't really exist outside of some very specific applications, as we as civilians would probably mostly be running around with 14.5" carbines and changing out muzzle devices as we damn well please.

But we have the laws that we have.

Kyle Reese
04-15-2012, 10:38 PM
I personally stick with the guns with proven track records over the long haul.

Buy whatever suits your fancy.

Same here. All of the M4 type carbines I've been issued downrange have been carbine length gas systems. I've had no issues regarding reliability or function.

BWT
04-17-2012, 11:16 PM
I need more details. :p

When you say "upper" are you talking about everything that resides in, and comes attached to, the upper receiver on a complete gun with the exception of the parts attached via the takedown and pivot pins? and including stock, plastic, handguards?

and, what barrel profile on the BCM, and can I change the 6920 upper to a 6720?

To answer my own questions, if you were giving me everything not attached to the two pins, and both barrels were lightweight, I'd take the Colt.

Which is NO slam on BCM. They are an awesome company, owned by the best guy I know in the industry, and they make a GREAT product.

Why? That'd be my only question. Maybe that might help some us understand. From the two different companies, why would you buy the same product from one Company over the other?

As for gas lengths, and honestly, this has driven into the which AR I would buy discussion. I like Mid-Length, I mean, the price difference of a BCM Midlength versus a 6920, barrel length/handguard length, my perception of wear on items (It runs at a few thousand lbs less pressure, and that's good enough for me, I mean, I don't care to debate it, if you think something running at higher pressure will last just as long then the same component running at lesser pressure, I'm not going to argue with you), better carrier dwell time in a Midlength versus a Carbine with the same barrel length, the barrel profile itself, having one of the best charging handles out there from the factory, a life time warranty, not having to ditch a carrying handle to buy a BUIS, and $150 price difference is why I went the route I did. I just can't find a logical conclusion to go Colt in a comparison of the two, again, for me, for the reasons listed above.

That being said, I don't think you'd have a reliability issue with either one, so I don't know how much I'd agonize over it.

I'm absolutely no SME, but I had a question, and I figured I'd throw in my .02$ on the matter.

If you want that 6920, go ahead and buy it.

ETA:


Same here. All of the M4 type carbines I've been issued downrange have been carbine length gas systems. I've had no issues regarding reliability or function.


Do you see a lot of Carbine length gas systems on 16'' Barrels in Afghanistan? I'm not trying to be disrespectful in the least when I ask this, but I figured you guys would be running probably true M4A1's, especially with the word issued.

rob_s
04-18-2012, 05:05 AM
So you already bought the BCM?

I don't honestly think any amount of "why" is going to change anyone's opinion. Nor do I think most people would understand 50% of the whys, want to take the time to read through it, and wouldn't just dismiss it as "oh that? well yeah, but I don't care about THAT. and having the mid-length gas tube is more important to me than THAT."

I'm not going to argue the point any further, as there is clearly a lot of... well a lot of outside influence on these discussions. There is nothing *wrong* with the mid-length gas system per se, but it also doesn't cure cancer, and the carbine-length doesn't cause it. There are all these internet catch-phrases that get tossed around about the mid-length but which virtually none of the people tossing them around actually understand, have firsthand knowledge of, or can explain beyond the cliche.

"lower operating pressure". OK. So what? What parts does that "save wear and tear" on? What is the failure rate of the carbine-length, measured in number of rounds fired, vs. the mid-length? How many of those parts have you seen fail?

"longer dwell time". OK. So what? What does that get you? and what is the trade-off? There ain't no free lunch, so there has to be something.

"more reliable". Really? Measured how? What cleaning interval? I define reliability as "the likelihood that the gun will go bang" and longevity as "the number of times it will go bang". How, exactly, does the mid-length help in either case? and what happens when it gets dirty? Do you think Mike Pannone's no-lube-test would have gone on as long with that lower-pressure mid-length?

I don't care what anyone buys, but when asked by a new shooter starting out I currently tell them to buy a Colt 6720, especially since right now they are often EASIER to find than a complete BCM, and often less expensive. I just wish people would stop parroting what they read on the internet or what their favorite SME told them to think and say, and engage their brains and think beyond the catch phrase.

I would HAPPILY take a BCM, and have three of them in my safe right now. At least one is a model you couldn't buy right now even if you wanted to. This is because I have a good relationship with Paul, find him to be one of the shining spots of integrity and knowledge in the darkness that is the gun bidness, and he appears to respect my opinion as well. I'm NOT slamming his products at all. In fact, he makes and sells carbine-length gas system barrels as well.

This topic is not about any one product, brand, or SME but is about 2" of gas tube length. If you shoot often and shoot well, I frankly don't care if you shoot a 7.5" DPMS with a pistol gas tube as long as it runs.

GJM
04-18-2012, 06:22 AM
Rob, to your point on the availability of BCM complete carbines, I have been led to believe that the important difference in an AR is in the upper, that there are relatively few manufacturers of lowers, and we shouldn't get hung up by what name is on the lower, assuming it contains the proper parts. Can you comment on this?

rob_s
04-18-2012, 08:09 AM
For those of us that have been into ARs since the ban, yes you are much less likely to get a lemon of a lower today than you were back then. But it's no guarantee. When people say that all lowers come from the same few places what they are talking about is the raw forgings, not the complete lowers as you are used to seeing them. What happens next, and who does it, still matters. I have a friend who got antsy and bought any old AR he found at the gunshow for what he thought was a good price and now his hammer and trigger pins are drifting out while firing. We'll have to correct it with the stupid KNS anti-roll pins to salvage the gun, or get him into a better gun altogether.

And my point here in talking about buying complete guns is new shooters or buyers. I see analysis paralysis in so many prospective buyers because they get locked into "well if I'm going to buy the upper separate, why not get the handguard I *want*?" and then they seize up for two months "researching" handguards online. Same for lowers and other parts.

BWT
04-18-2012, 07:58 PM
So you already bought the BCM?

I don't honestly think any amount of "why" is going to change anyone's opinion. Nor do I think most people would understand 50% of the whys, want to take the time to read through it, and wouldn't just dismiss it as "oh that? well yeah, but I don't care about THAT. and having the mid-length gas tube is more important to me than THAT."

I'm not going to argue the point any further, as there is clearly a lot of... well a lot of outside influence on these discussions. There is nothing *wrong* with the mid-length gas system per se, but it also doesn't cure cancer, and the carbine-length doesn't cause it. There are all these internet catch-phrases that get tossed around about the mid-length but which virtually none of the people tossing them around actually understand, have firsthand knowledge of, or can explain beyond the cliche.

"lower operating pressure". OK. So what? What parts does that "save wear and tear" on? What is the failure rate of the carbine-length, measured in number of rounds fired, vs. the mid-length? How many of those parts have you seen fail?

"longer dwell time". OK. So what? What does that get you? and what is the trade-off? There ain't no free lunch, so there has to be something.

"more reliable". Really? Measured how? What cleaning interval? I define reliability as "the likelihood that the gun will go bang" and longevity as "the number of times it will go bang". How, exactly, does the mid-length help in either case? and what happens when it gets dirty? Do you think Mike Pannone's no-lube-test would have gone on as long with that lower-pressure mid-length?

I don't care what anyone buys, but when asked by a new shooter starting out I currently tell them to buy a Colt 6720, especially since right now they are often EASIER to find than a complete BCM, and often less expensive. I just wish people would stop parroting what they read on the internet or what their favorite SME told them to think and say, and engage their brains and think beyond the catch phrase.

I would HAPPILY take a BCM, and have three of them in my safe right now. At least one is a model you couldn't buy right now even if you wanted to. This is because I have a good relationship with Paul, find him to be one of the shining spots of integrity and knowledge in the darkness that is the gun bidness, and he appears to respect my opinion as well. I'm NOT slamming his products at all. In fact, he makes and sells carbine-length gas system barrels as well.

This topic is not about any one product, brand, or SME but is about 2" of gas tube length. If you shoot often and shoot well, I frankly don't care if you shoot a 7.5" DPMS with a pistol gas tube as long as it runs.


So you already bought the BCM?

I bought one, I liked it. My father bought one for himself as well.


I don't honestly think any amount of "why" is going to change anyone's opinion. Nor do I think most people would understand 50% of the whys, want to take the time to read through it, and wouldn't just dismiss it as "oh that? well yeah, but I don't care about THAT. and having the mid-length gas tube is more important to me than THAT."

I would like to know, I'm not most people, I don't care what most people perceive, or what your perception is of most people. I asked, if you don't want to share, that's cool, but this is a thread asking for information, I figured, if you're going to offer an opinion, you might want to delve into the reasons behind it, I promise you, I will not be overwhelmed with information. I entered the discussion and I asked you because I wanted to know.


I'm not going to argue the point any further, as there is clearly a lot of... well a lot of outside influence on these discussions. There is nothing *wrong* with the mid-length gas system per se, but it also doesn't cure cancer, and the carbine-length doesn't cause it. There are all these internet catch-phrases that get tossed around about the mid-length but which virtually none of the people tossing them around actually understand, have firsthand knowledge of, or can explain beyond the cliche.

Understood, there's a lot of buzz words, so granted, people band wagon, it's true.


"lower operating pressure". OK. So what? What parts does that "save wear and tear" on? What is the failure rate of the carbine-length, measured in number of rounds fired, vs. the mid-length? How many of those parts have you seen fail?

Now to the meat of the discussion. It runs at higher pressures, period, it puts more pressure in the carrier, ask any engineer, they'll say less pressure and stress on a component is good, regardless. I mean, honestly, here's what it boils down to me. Why don't people run a Mid Length Gas on an 18'' Barrel? Why? Because it makes no sense when you can run a rifle or intermediate length, same logic applies, IMHO. As far as carriers, most guys around here replace their BCG's (Yourself included I'm fairly certain) at 7,500-10,000 rounds, that being said, Pat Rogers ran his first M16 BCG in a BCM rifle to what 15-16,000 rounds? You don't run your carrier to destruction, you run it within it's predicted service life, so honestly, you probably will never see a BCG fail, that means in your case if you run in a Carbine or Midlength gas system that a BCG, will likely never fail, because you've replaced it before it broke, and I'm speaking to you personally. When you replace that component at that rate, it's likely you should never expect a failure.

Let's further broach the subject, how frequently do you replace your BCG's? What's the most rounds you have on a single gun with a M16 BCG.

Also, to expound upon this, let's talk about Midlength recoil pressure, my opinion, it's less felt recoil, I mean, is the .223 a man slayer in the regards to recoil? No, and if you can afford $1,000-1,200 base rifle, you can afford $40-60 (or $400) compensators, etc. I also think that 7.62x39mm is very controllable, just my opinion. But, again, it is a benefit.


"longer dwell time". OK. So what? What does that get you? and what is the trade-off? There ain't no free lunch, so there has to be something.

More flexible in ejection/extraction of certain cartridges, you can take a wider variety of rounds at higher and lower pressures and expect a more reliable rifle. How much more reliable? (Again, 6920, my opinion, lubricated, run with heck even wolf .223 ammo, you should never experience a weapon related malfunction, ever.) I don't know the exact percentages, but it is more reliable, how much more tangible is it? I'd have to do more research.


"more reliable". Really? Measured how? What cleaning interval? I define reliability as "the likelihood that the gun will go bang" and longevity as "the number of times it will go bang". How, exactly, does the mid-length help in either case? and what happens when it gets dirty? Do you think Mike Pannone's no-lube-test would have gone on as long with that lower-pressure mid-length?

Possibly, honestly, with less gas pressure coming back in the gun, there'd be less gas running through the gun and out the vent holes. My opinion, a gun running the same heat at less pressure's metal will fatigue less, will be worn less and will be stressed less. You add heat to a component, then you add pressure, you vary that pressure and you will see your varying degrees of wear, this gets back to lower operating pressure.

http://en.wikipedia.org/wiki/Heat_capacity

So I think you'd see less parts fatigue, how significant is that? Debatable, but I think it's going to play a part in time, just out of general universal principles, if you run the same component at 25,000 lbs of pressure versus 22,000, that same component will last longer and will have less wear at 22,000. It's just... how it is.

Alright let's delve into area of reliability, that a laymen (not going to not put myself in that segment, I know what I do for a living, and it's not carrying a gun) may not have understood, Lebowski broached the topic.


Handguards abound to give you a better forward grip, extractor upgrades are less than $5, and as already mentioned, there's no quantifiable data on middys versus carbine except for maybe EAG's well known (and laudable) data keeping on malfunctions in their courses.

Since it is known that carbines run at higher pressures and have a faster carrier movement, they must ideally have a black insert and a o-ring on that insert under the extractor, to promote reliable extraction, because they were finding reliability issues.

Let me ask you this, would you run a carbine length gas system without a black insert and o-ring? No. No you wouldn't, because you know, that's not the best idea. (ETA: To further branch out this, because we *know* that the carbine length gas system is a higher pressure gas system, there's no dancing around it, it is also recommended you replace your extractor and black insert and your o-ring at 5,000 round intervals, again, a preventative maintenance, like replacing a BCG at 7,500-10,000, will probably ensure that regardless of what gun you run, you will see it run reliably, if we were in a discussion where most of the individuals here weren't aware of the life cycle of a weapon, and when to replace certain components, I think you'd start to see things like Midlength verus Carbine length play a bit more of a role)


I don't care what anyone buys, but when asked by a new shooter starting out I currently tell them to buy a Colt 6720, especially since right now they are often EASIER to find than a complete BCM, and often less expensive. I just wish people would stop parroting what they read on the internet or what their favorite SME told them to think and say, and engage their brains and think beyond the catch phrase.

I would HAPPILY take a BCM, and have three of them in my safe right now. At least one is a model you couldn't buy right now even if you wanted to. This is because I have a good relationship with Paul, find him to be one of the shining spots of integrity and knowledge in the darkness that is the gun bidness, and he appears to respect my opinion as well. I'm NOT slamming his products at all. In fact, he makes and sells carbine-length gas system barrels as well.

This topic is not about any one product, brand, or SME but is about 2" of gas tube length. If you shoot often and shoot well, I frankly don't care if you shoot a 7.5" DPMS with a pistol gas tube as long as it runs.

I agree with all of this, except, I just don't like Colt's warranty, or the configuration (carrying handle, charging handle, etc, when you can get (in my opinion, again, emphasis on my opinion, this isn't a basis in fact, just my perference) a more ideally setup rifle as far as a flat top and charging handle configuration from the factory and I personally wouldn't want a light weight barrel, but that's me. As someone who wants a BCM SBR, I absolutely understand the they're not everywhere argument, but, I think it offers a lot that, not a lot of people consider. I don't think it's a bad recommendation, I just wouldn't buy it over a Midlength quality AR, that being said, I would buy a Daniel Defense Mid-length AR if they came without rails and I was in the market.

Look forward to your reply.

ETA 2: I'd also like to add, if anyone wants to rest on the as it's been referred to as "Mountain of Data" that proves the Carbine length gas system is reliable, I'm going to go ahead and make the logical extension, that you're referring to either the Military's records or Law Enforcement Branch's records with that. That tid bit being said, a 16'' Carbine Length AR is a different animal from a 14.5'' Carbine Length AR. As I understand it, honestly, the only reason we ever ended up with an 14.5'' barrel was they wanted a rifle with the shortest possible gas length that could run reliably, similar to an M16, that they could mount a bayonet too, thus, the M4A1 Carbine. ETA 3: Forgot to state the obvious, most institutions like the Military and Law Enforcement aren't using 16'' Carbine Length rifles in their SWAT Teams, AFAIK, what an officer uses as a patrol rifle, probably a different story, I'd say it'd be reasonable to expect an individual officer to purchase a 6920. But I wouldn't expect 95% of officers to use a 6920 to the extent that SWAT Teams use their M4A1's.

DocGKR
04-18-2012, 11:44 PM
I've got to agree with a lot of what BWT wrote above. I've sat in meetings about a decade ago with reps from military SOF units who were complaining about the vast numbers of M4 bolts they were breaking as training round counts ramped up after 9/11. As Pat Rogers and others who have run multiple carbines hard have noted anecdotally, the bolts in the mid-length AR15's seem to last about twice as long as those in carbine length AR's.

Odin Bravo One
04-19-2012, 02:08 AM
I don't know how often I break a bolt, but it is often enough that I carry a spare on my gear............just in case. Will a mid-length system fix it? Prolong the service life? Dunno..........don't care much really either. We are SEVERAL THOUSANDS of dollars worth of ammo downrange before that happens. If you are balking at the cost of a replacement bolt, do the math on the ammo cost to get there. $200 for a bolt (way high estimate) is chump change compared to what you forked out on bullyats to get to that point.

Buy what suits your fancy. Anyone can come up with any reason to justify their trinket, gizmo, gadget, do-hickey, rifle selection, gas system, gas piston, whatever. A lot of time and Kb's have been poured into the topic of "which?" that is probably better off just buying and learning, and training.

The Wizard, not the wand is what decides 99.99999% of the confrontations where a carbine is used/necessary.

BWT
04-20-2012, 11:08 PM
I've got to agree with a lot of what BWT wrote above. I've sat in meetings about a decade ago with reps from military SOF units who were complaining about the vast numbers of M4 bolts they were breaking as training round counts ramped up after 9/11. As Pat Rogers and others who have run multiple carbines hard have noted anecdotally, the bolts in the mid-length AR15's seem to last about twice as long as those in carbine length AR's.

I did not know that, thank you for sharing.


I don't know how often I break a bolt, but it is often enough that I carry a spare on my gear............just in case. Will a mid-length system fix it? Prolong the service life? Dunno..........don't care much really either. We are SEVERAL THOUSANDS of dollars worth of ammo downrange before that happens. If you are balking at the cost of a replacement bolt, do the math on the ammo cost to get there. $200 for a bolt (way high estimate) is chump change compared to what you forked out on bullyats to get to that point.

Buy what suits your fancy. Anyone can come up with any reason to justify their trinket, gizmo, gadget, do-hickey, rifle selection, gas system, gas piston, whatever. A lot of time and Kb's have been poured into the topic of "which?" that is probably better off just buying and learning, and training.

The Wizard, not the wand is what decides 99.99999% of the confrontations where a carbine is used/necessary.

Honestly, I'm going to agree, it's kind of like I alluded to in the thread earlier, we're talking about guns that start at $1,000. If you're shooting 5.56mm brass, it's going to be $.30-.37 a round if you're shoot steel cased polymer coated .223 Rem it's going to be around $.21-26 a round. A thousand rounds of either is going to cost more than an a new M16 BCG from any manufacturer, it's true. You can spend $400-800 on a quality Red Dot.

Let's say you replace your M16 BCG at 7,500 rounds on the dot at 5.56mm costing let's go to ammo man, go with 55 gr prvi 5.56mm, http://www.ammoman.com/p/5/223-556-privi-partizan that goes $370 a case, shipped.

That's $2775 in bullets. Almost paid for your rifle three times (depending on which rifle you go with)

Going with Wolf from the same source, shipped, http://www.ammoman.com/p/199/223-wolf-55-grain-in-sealed-tins at $270.

That's $2075 in bullets, alone. Paid for your rifle twice.

Not calculating magazines you'll wear out, what you'll spend on lubrication and cleaning equipment, I'd say you could add another $100-200 (probably closer to 3-4, depending on the magazines, I mean that's still 7,000 rounds through dumping the magazines on concrete, loading, wear, stepping on, whatever) to either figure to get the amount in magazines and lubrication (I mean we're talking 7,500 rounds), before you replace a $139 component.

Cumulatively does it *matter* from a cost savings perspective? I'd say the differences in price... are you really going to notice it if you train with the kind of intensity that an institution uses? Probably not, a Carbine class being the exception I probably shoot around a 1,000 rounds through my AR a year, that's 5-6 Carbine Matches, and then just shooting in general, maybe 1,200-1,400. But about 150 per person per match, if I decided to shoot it and I go with my Brother and we both share it, that's 300, and if it goes to the range, 100-150-ish, so let's say it sees... actually I calculated it, that's about 1,500 rounds a year through that single firearm. That means I could go... 5 years at that rate without changing it.

So it definitely lends a lot of credibility to Sean's point.

That being said, I think the Midlength is better for the reasons outlined in my earlier post, in regards to pressure levels and the inherent affects on the B.C.G, extraction, dwell time, appearance, handguard length, (ETA: These last two are purely my opinion, and honestly, you could throw a rail on a carbine length and that would void that benefit) etc. but truthfully, when you look at the data that way, and you keep things in perspective, for the average buyer, it's not going to make a huge deal one way or another. Also rob hit on another point... IMHO, good luck finding a 6920 at most neighborhood gun stores, and even more further good luck to you finding a quality Mid length, with the internet, it's easier, but I bought my rifle without handling one, I had handled a carbine length, but not a midlength.

To bring it back to focal point of this thread, someone asked the versus, and I wanted to give my honest opinion, and that's it. I think the Midlength is an overall better system within the context of that barrel length, I do, but I'd say better incrementally in many places. Outstandingly, don't get a carbine better? Not exactly. I mean it's like this, on the front of pistol-training.com a few weeks back ToddG posted a comparison of how well he shot with the Crimson Trace grips versus the standard sights, I think he did at most 10% better in some drills. Some there was no difference. (No Joke, I went to reference that data, thinking, let's just go ahead and grab the info and he's posted the second portion of the series)

http://pistol-training.com/archives/6480

http://pistol-training.com/archives/6504

I'd see this as a comparable situation, is that difference worth it to the end user, well, let the end user decide that, if you service your 16'' Carbine Length rifle at the proper intervals, you will never experience an issue IMHO, especially not with a Colt 6920. Same story with a Mid length.

I want to say thank you to all the people that participated in this thread, like just looking at it, this would be a 30-40 page topic on other forums with the same amount of words of wisdom to be gleaned, but here, there's just a ton of information and qualified information as well. I also like that this isn't much of a debate as much as it is sharing information.

Anyway, that's all I've got now.

Brandon

Steve S.
04-21-2012, 11:52 PM
Should a user have to KNOW why a midlength is easier on the internals as compared to a carbine in order to own one?

Do they need to measure to prove its softer shooting, or does applying the fundamental knowledge of the operating system and trusting theory (as well as many documented user reports) cut it?

As for the argument on replacing bolts and that they are cheap - but why not choose the more durable option to begin with?

There are ABSOLUTELY free lunches. It's called progression. People use to believe you couldn't get a vehicle to go faster without it using more fuel. Guess what? My neighbors mini van is faster and much more fuel efficient than my other neighbors old Mustang. It is entirely possible to have improvements without a trade off. The carbine system was a compromise of the M16. Want a shorter barrel? Here's what you have to do... The midlength just bridges the gap. Maybe the midlength is placing the gas block where it should have been in the first place when making the M4? It's one way of looking at it. If so, then it is an "improvement" and not a "trade off".

You want the longest sight radius possible, and a taper pinned fixed front sight is the business in fighting guns. This doesn't even get into modern shooting methods and support hand placement. If a midlength will run as reliably as its carbine brethren - it is an improvement. I personally don't think anything needs to be measured to confirm this - as far as operating pressures are concerned - because the sight radius is a big improvement in and of itself. Anything else is just icing on the cake.

As far as the TDP... as much as it is a means to control quality - it is a promise of stagnation in improvements.

This is just my $0.02 on the "midlength vs carbine" debate. Worth what you paid for it....

rob_s
04-22-2012, 08:00 AM
As far as the TDP... as much as it is a means to control quality - it is a promise of stagnation in improvements.

I tend to stay away from the "it's milspec" defense, but the sad truth is that the TDP is like a building code, the lowest standard, and yet only one company (well, two if the Remington stories are true) meets it. If you're going to "exceed" it, or even just be "just as good" in a different way than specified, you have to be able to prove it. and we shouldn't go changing things just to change the. Different isn't better, better is better.

Are there (potentially) ways to improve upon it? Of course. Is anyone doing it? I don't know. A lot sure claim to, without any real numbers or anything else to back them up.


Should a user have to KNOW why a midlength is easier on the internals as compared to a carbine in order to own one?

Own one? No, you can own whatever you want. But if you're going to go around suggesting something you ought to have more than "so and so said so". If so and so said so, why did they say so and based on what? If you don't have the numbers and didn't generate the numbers, I sure hope that whoever you're quoting does and you can regurgitate more than "because they said so" and can share the numbers with us.

This is the crux of my issue with the mid-length craze of late. Everyone is just going around repeating how great the emperor's new clothes are. I'm not so much lambasting the mid-length or a specific maker as I am how easily people just launch into a decision totally blind and then expend unbelievable amounts of energy defending that. People tell me they don't have time to go do an empirical test of their own but they do have time to get on the internet and argue the point to death with me.

I don't know if the claims about the mid-length are true or not. But neither does anyone else in this thread yet they feel compelled to make declarative and shallow statements (evidently based largely on justifying their own purchases). As an example, "lower pressure". Let's say that's true. Let's accept that as true in spite of the fact that there are no numbers given to substantiate it. So what? The next step is proving WHY THAT MATTERS. You don't just stop at "well it imparts 12.76% less pressure into the BCG", you have to go on to say why that matters, what the effective reduction on "felt recoil" is and what the increase is on parts life (if those are your claims). Saying "isn't it obvious that lower pressure increases life and reduces recoil?" doesn't cut it. Well, evidently it does on the internet, but not in the real world. and you also need to be able to respond to any counter claims relative to the negative effects of that reduced pressure, such as a shorter operating time due to ore rapidly burning off of lube and buildup of carbon and other crud in the system.

The good news is that this continual discussion here and elsewhere and lack of data has led me to work on my own testing. I'm hoping to source two otherwise identical barrels with the sole exception of gas port location and size soon. I will then need to work on adjustable gas blocks for both as well as methods to bring the overall weight and center of gravity to identical levels for both.

jmjames
04-22-2012, 08:32 AM
The good news is that this continual discussion here and elsewhere and lack of data has led me to work on my own testing. I'm hoping to source two otherwise identical barrels with the sole exception of gas port location and size soon. I will then need to work on adjustable gas blocks for both as well as methods to bring the overall weight and center of gravity to identical levels for both.

I, for one, would very much welcome that information, and I am sure a lot of others will too. I am actually pretty surprised that no one with a horse in the mid-length race like DD or BCM has done a test like this and published the results, unless, of course, the numbers were not favorable to them. :)

J.Ja

Steve S.
04-22-2012, 01:07 PM
I tend to stay away from the "it's milspec" defense, but the sad truth is that the TDP is like a building code, the lowest standard, and yet only one company (well, two if the Remington stories are true) meets it. If you're going to "exceed" it, or even just be "just as good" in a different way than specified, you have to be able to prove it. and we shouldn't go changing things just to change the. Different isn't better, better is better.

Are there (potentially) ways to improve upon it? Of course. Is anyone doing it? I don't know. A lot sure claim to, without any real numbers or anything else to back them up.


Own one? No, you can own whatever you want. But if you're going to go around suggesting something you ought to have more than "so and so said so". If so and so said so, why did they say so and based on what? If you don't have the numbers and didn't generate the numbers, I sure hope that whoever you're quoting does and you can regurgitate more than "because they said so" and can share the numbers with us.

This is the crux of my issue with the mid-length craze of late. Everyone is just going around repeating how great the emperor's new clothes are. I'm not so much lambasting the mid-length or a specific maker as I am how easily people just launch into a decision totally blind and then expend unbelievable amounts of energy defending that. People tell me they don't have time to go do an empirical test of their own but they do have time to get on the internet and argue the point to death with me.

I don't know if the claims about the mid-length are true or not. But neither does anyone else in this thread yet they feel compelled to make declarative and shallow statements (evidently based largely on justifying their own purchases). As an example, "lower pressure". Let's say that's true. Let's accept that as true in spite of the fact that there are no numbers given to substantiate it. So what? The next step is proving WHY THAT MATTERS. You don't just stop at "well it imparts 12.76% less pressure into the BCG", you have to go on to say why that matters, what the effective reduction on "felt recoil" is and what the increase is on parts life (if those are your claims). Saying "isn't it obvious that lower pressure increases life and reduces recoil?" doesn't cut it. Well, evidently it does on the internet, but not in the real world. and you also need to be able to respond to any counter claims relative to the negative effects of that reduced pressure, such as a shorter operating time due to ore rapidly burning off of lube and buildup of carbon and other crud in the system.

The good news is that this continual discussion here and elsewhere and lack of data has led me to work on my own testing. I'm hoping to source two otherwise identical barrels with the sole exception of gas port location and size soon. I will then need to work on adjustable gas blocks for both as well as methods to bring the overall weight and center of gravity to identical levels for both.

Couldn't agree more. I'm sure Rob realizes, if nobody else does, that I'm playing a bit of Devil's Advocate. I don't own any midlengths, so I can't speak on them one way or the other. I have two midlength barrels on hand, but that was more because of the awesome deal a friend secured me. I guess I'll see what all the fuss is about when I can find some upper receivers in stock somewhere. :mad:

As for the good news.... I knew it would happen. We all win. :) Poke Rob enough times and he will put the rubber to the road. And that's why we love you, Rob. I look forward to this. So I can tell people how their carbine sucks or how their midlength doesn't do anything better then my carbines. Yes, I drink Hater-aide every morning...

Little Creek
04-23-2012, 02:24 PM
Couldn't agree more. I'm sure Rob realizes, if nobody else does, that I'm playing a bit of Devil's Advocate. I don't own any midlengths, so I can't speak on them one way or the other. I have two midlength barrels on hand, but that was more because of the awesome deal a friend secured me. I guess I'll see what all the fuss is about when I can find some upper receivers in stock somewhere. :mad:

As for the good news.... I knew it would happen. We all win. :) Poke Rob enough times and he will put the rubber to the road. And that's why we love you, Rob. I look forward to this. So I can tell people how their carbine sucks or how their midlength doesn't do anything better then my carbines. Yes, I drink Hater-aide every morning...

I just want a midlength because I find my carbine length handguard too short.

BWT
04-25-2012, 07:39 PM
I tend to stay away from the "it's milspec" defense, but the sad truth is that the TDP is like a building code, the lowest standard, and yet only one company (well, two if the Remington stories are true) meets it. If you're going to "exceed" it, or even just be "just as good" in a different way than specified, you have to be able to prove it. and we shouldn't go changing things just to change the. Different isn't better, better is better.

Are there (potentially) ways to improve upon it? Of course. Is anyone doing it? I don't know. A lot sure claim to, without any real numbers or anything else to back them up.


Own one? No, you can own whatever you want. But if you're going to go around suggesting something you ought to have more than "so and so said so". If so and so said so, why did they say so and based on what? If you don't have the numbers and didn't generate the numbers, I sure hope that whoever you're quoting does and you can regurgitate more than "because they said so" and can share the numbers with us.

This is the crux of my issue with the mid-length craze of late. Everyone is just going around repeating how great the emperor's new clothes are. I'm not so much lambasting the mid-length or a specific maker as I am how easily people just launch into a decision totally blind and then expend unbelievable amounts of energy defending that. People tell me they don't have time to go do an empirical test of their own but they do have time to get on the internet and argue the point to death with me.

I don't know if the claims about the mid-length are true or not. But neither does anyone else in this thread yet they feel compelled to make declarative and shallow statements (evidently based largely on justifying their own purchases). As an example, "lower pressure". Let's say that's true. Let's accept that as true in spite of the fact that there are no numbers given to substantiate it. So what? The next step is proving WHY THAT MATTERS. You don't just stop at "well it imparts 12.76% less pressure into the BCG", you have to go on to say why that matters, what the effective reduction on "felt recoil" is and what the increase is on parts life (if those are your claims). Saying "isn't it obvious that lower pressure increases life and reduces recoil?" doesn't cut it. Well, evidently it does on the internet, but not in the real world. and you also need to be able to respond to any counter claims relative to the negative effects of that reduced pressure, such as a shorter operating time due to ore rapidly burning off of lube and buildup of carbon and other crud in the system.

The good news is that this continual discussion here and elsewhere and lack of data has led me to work on my own testing. I'm hoping to source two otherwise identical barrels with the sole exception of gas port location and size soon. I will then need to work on adjustable gas blocks for both as well as methods to bring the overall weight and center of gravity to identical levels for both.

You ever going to tell us why you'd pick Colt?

Jay Cunningham
04-25-2012, 07:48 PM
He did, numerous times.

BWT
04-25-2012, 11:14 PM
He did, numerous times.



I don't honestly think any amount of "why" is going to change anyone's opinion. Nor do I think most people would understand 50% of the whys, want to take the time to read through it, and wouldn't just dismiss it as "oh that? well yeah, but I don't care about THAT. and having the mid-length gas tube is more important to me than THAT."

I would like to know, I'm not most people, I don't care what most people perceive, or what your perception is of most people. I asked, if you don't want to share, that's cool, but this is a thread asking for information, I figured, if you're going to offer an opinion, you might want to delve into the reasons behind it, I promise you, I will not be overwhelmed with information. I entered the discussion and I asked you because I wanted to know.

This is from the last page, which was preceded (ETA 2: preceded not proceeded) by this.



Originally Posted by rob_s
I need more details.

When you say "upper" are you talking about everything that resides in, and comes attached to, the upper receiver on a complete gun with the exception of the parts attached via the takedown and pivot pins? and including stock, plastic, handguards?

and, what barrel profile on the BCM, and can I change the 6920 upper to a 6720?

To answer my own questions, if you were giving me everything not attached to the two pins, and both barrels were lightweight, I'd take the Colt.

Which is NO slam on BCM. They are an awesome company, owned by the best guy I know in the industry, and they make a GREAT product.
Why? That'd be my only question. Maybe that might help some us understand. From the two different companies, why would you buy the same product from one Company over the other?

Why? That'd be my only question. Maybe that might help some us understand. From the two different companies, why would you buy the same product from one Company over the other?

I mean, I hope he really says because they make Mil-Spec M4's, because for two reasons I'm going to tell him he's wrong, or that his mountain of data is wrong. One, I love how quickly the Government just dropped Colt as their Sole Source Provider for M4's, which, honestly, kind of damages the "Colt's been in this business a long time... Hey, You know, they've been making M16's since before you were born. They're the only *real* M4's" Two, The M4A1 is a Select-Fire 14.5'' Carbine, not a Semi Auto 16'' barrel Carbine, because I can imagine that's where the data is alluded to comes from.

As a side note, I'd invite people who have suggested that they have a lot of data, to be forth coming about it, and it at this point, go ahead and cites your sources to go ahead and educate all of us on where exactly you have drawn your conclusions. Maybe that'll take the "play" out of this discussion.

He also never answered how long he runs Bolt Carrier Groups, he also never addressed the Black Insert objection/extraction implication.

He came down to the fact that it runs at 12.7% less pressure, and then implies that because People haven't posted reports (By the way, since this is becoming a "debate" I'd invite rob, to go ahead and pull out his data on the 6920 that he's clearly got, and he better have it. Oh he better have it, otherwise, he's a band wagoner as well, because... Nobody tested a 16'' Carbine Length Rifle, they tested a 14.5'', which voids the relevance of it for this apparent intense online debate) documenting hundreds of thousands of rounds down range, that it's hearsay, that one can't use deductive reasoning, that there's no basis in fact.

I let all of that go, but...

Don't tell me he answered why Jay. Because he specifically told me, he wasn't going to.

Getting back to the last post.


This is the crux of my issue with the mid-length craze of late. Everyone is just going around repeating how great the emperor's new clothes are. I'm not so much lambasting the mid-length or a specific maker as I am how easily people just launch into a decision totally blind and then expend unbelievable amounts of energy defending that. People tell me they don't have time to go do an empirical test of their own but they do have time to get on the internet and argue the point to death with me.

I don't know if the claims about the mid-length are true or not. But neither does anyone else in this thread yet they feel compelled to make declarative and shallow statements (evidently based largely on justifying their own purchases). As an example, "lower pressure". Let's say that's true. Let's accept that as true in spite of the fact that there are no numbers given to substantiate it. So what? The next step is proving WHY THAT MATTERS. You don't just stop at "well it imparts 12.76% less pressure into the BCG", you have to go on to say why that matters, what the effective reduction on "felt recoil" is and what the increase is on parts life (if those are your claims). Saying "isn't it obvious that lower pressure increases life and reduces recoil?" doesn't cut it. Well, evidently it does on the internet, but not in the real world. and you also need to be able to respond to any counter claims relative to the negative effects of that reduced pressure, such as a shorter operating time due to ore rapidly burning off of lube and buildup of carbon and other crud in the system.

The good news is that this continual discussion here and elsewhere and lack of data has led me to work on my own testing. I'm hoping to source two otherwise identical barrels with the sole exception of gas port location and size soon. I will then need to work on adjustable gas blocks for both as well as methods to bring the overall weight and center of gravity to identical levels for both.

He then goes onto imply it's a craze, and how it's a fashion, and how we've all been deceived, I've gone in great detail on why I think what I think.

Empirical data is basically stating, why haven't I spent $10,000 to prove my point? (Let's calculate 10,000 rounds of 5.56mm at $360 a case ending up at $3,600 times two, being $7200, Plus a $1150 6920 and a essentially $1050 Midlength Carbine, it'd actually be around $9400, but with tax, let's just say $9500.) Because, I'd need honestly.... probably about 10,000 rounds of 5.56mm per gun and a Host Midlength Gun and a Host Carbine Length, and run them both at the same intervals under the same conditions and then capture the data as it's tested to log it. And guess what you can do at that point, if I spent that money, because I'm a band wagoner, right, and I've proven to the internet that I have proven beyond the shadow of a doubt that the Midlength is Superior... Then you run into laws of statistics, where what constitutes a good group? 5? 10? 30? So would I need to run somewhere between a half dozen and 30 rifles from the exact same batch with the same batch of bullets (all made at the same factory with the same tooling with the same projectiles, from the same lot) to scientifically prove that a system running at less pressure is truly more effective?

So then I must debate the relevancy of statistics, go ahead and say that's unrealistic and go look at any of the independent silencer testing's websites and the lengthy debates they've had on the relevancy of dB reduction and how it was measured.

Intense Internet debating, I'm telling ya. All that aside, I hold a perspective, but it's just a discussion.

Anyway, I'm going to go ahead and say this because I feel it's important, I'm a Christian, and I really hate for things to take a biting, dark perspective that this exchange is wearing down to, and for that I apologize, but... unless you see something drastically different, do you see where he stated the why Jay?

As a side note, I'd like to kind of dial it down the intensity a bit and have a discussion. I'm interested to see what rob_s has in mind for testing purposes.

ETA: Removed a quote.

rob_s
04-26-2012, 06:39 AM
You ever going to tell us why you'd pick Colt?

I don't think there's any point. Pigs and mud and all that.

This thread turned into the battle of the SMEs where we are only going to quote and pick and choose from the ones that support our positions. I'm over that. Big time. I know enough about the system to be my own SME and make up my own mind. I'm not going to argue from experience against people that only have quotes and links to substantiate their positions, and to use to defend the purchases they already made. It's pointless.

pigs and mud.

rob_s
04-26-2012, 06:42 AM
I just want a midlength because I find my carbine length handguard too short.

Absolute best reason to choose one, and nobody can argue with it as it's verifiable (everyone can measure 7" vs. 9") and subjective (YOU prefer the longer handguard). The second best reason, by a hair, is "longer sight radius" which again is verifiable and subjective.

BWT
04-29-2012, 09:50 PM
I don't think there's any point. Pigs and mud and all that.

This thread turned into the battle of the SMEs where we are only going to quote and pick and choose from the ones that support our positions. I'm over that. Big time. I know enough about the system to be my own SME and make up my own mind. I'm not going to argue from experience against people that only have quotes and links to substantiate their positions, and to use to defend the purchases they already made. It's pointless.

pigs and mud.

That's fine.

Just being 100% honest with you, your review on BCM products, and your opinion on it, the article you wrote, among a few others, in all honesty, lead me to buying a BCM, and I ended up buying a Mid-length. You lead me away from Anvil Arms stripped lowers before they went bankrupt telling me they were a bad company, and you talked me into a complete lower assembly, which was a good choice, and for that I'd say Thank you.

You may not remember, it was awhile ago, but, it was back when you were a Moderator on Silencertalk, but anyway, look forward to your test results.