Buffer question(s)

[Darth_Uno]

I’ve been running my AR pistols (all with 11.5-12.5” barrels) with carbine buffers, and zero problems. Other than shooting softer, is there a reason to start fiddling around with other buffers? Again, I’ve had no reliability issues whatsoever, so if ain’t broke...

I also make it a point to shoot 5.56 (not .223) and generally avoid cheap ammo if that matters.

I skimmed the SBR/pistol thread and didn’t see this addressed directly.


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[Wingate's Hairbrush]

If it's working for you, no signs of premature wear in the rifle, and you're changing springs on an appropriate schedule, it certainly isn't necessary to swap out the buffer, especially if you're not shooting suppressed or planning to.

That said, most dedicated AR shooters are at least running H and often H2, which is food for thought because they tend to know what they're doing -- I'm not aware of anyone running a carbine buffer at 16" or shorter.

[rd62]

Not an expert, but I'd say potential parts longevity.

I run heavier in my 10.5 but that doesn't necessarily mean you should.

Someone more educated than me about it should be along.

[Casual Friday]

The operation and cycling of an AR is a balance of gas port size, ammo selection, and the buffer and spring. I would only run a carbine buffer if my gun was under gassed and wouldn't reliably cycle and lock back after the last round with common ammo when using a H buffer.

I run the heaviest buffer I can while maintaining 100% reliability with several ammo types, along with shooting in the cold weather. Most shorties will run all the way up to a H3 buffer with 5.56 loads, and some will still run with the H3 and cheap ammo like Tula, depending on the size of the gas port. Barrels that are a little more conservatively gassed will do better with an H2.

I'm not recoil sensitive in the least, but my nephew's PSA 10.5" build kit he bought was downright violent with the supplied carbine buffer and cheap spring. The KAK Shockwave blade didn't do it any favors in the comfort department either. I talked him into the A5 system and a SBA3 brace and that tamed it down nicely.

My 6933 with the A5H2 buffer and VLTOR spring runs like a scalded cat with just about any ammo, and shoots softer than many 16" guns. Very little red dot movement shot to shot.

TL;DR version: My vote is buy an H, H2, and maybe even H3 buffer and see for yourself. Or don't listen to me at all and just fuckin send it. #yolo (https://pistol-forum.com/usertag.php?do=list&action=hash&hash=yolo)

[TGS]

I’ve been running my AR pistols (all with 11.5-12.5” barrels) with carbine buffers, and zero problems. Other than shooting softer, is there a reason to start fiddling around with other buffers? Again, I’ve had no reliability issues whatsoever, so if ain’t broke...


No.

[Darth_Uno]

That said, most dedicated AR shooters are at least running H and often H2, which is food for thought because they tend to know what they're doing --

That's my thinking. If everyone who knows more than me does it, I should probably find out why.

[Darth_Uno]

No.

Exactly. I don't want to be the "works for me" guy. Hence, this thread.

[TGS]

Exactly. I don't want to be the "works for me" guy. Hence, this thread.

Heavy buffers in AR15s generally came about because of over-gassing.

If you're not suffering from your rifle being overgassed, you don't need a heavier buffer. I would actually be kind of concerned about an 11.5-12.5" shooting 5.56 with a Carbine buffer that still ejects consistently at 5 O'Clock and doesn't rip caseheads out.....but if it works, it works. If I had that rifle, I'd probably start playing around with heavier buffers just to see how it reacts, and pin-gauge the gas port to see if it's actually undersized (suspecting a cut down 14.5"-16" barrel with .0625" gas port not opened up)....but that's all academic for curiosity's sake. If the rifle is working fine, it's working fine.

ETA: If you come across some common .223 and it short strokes with an H buffer, I would put money that you've got a barrel that was cut-down from 14.5-16" without having the gas port opened up (or done so without good QA, or purposely limited like a Sionics RGP barrel), which is why you're shooting 5.56 with a carbine buffer and it's working fine. If it doesn't change function at all, you've just got a unicorn, enjoy it and drive on.

[Darth_Uno]

Both uppers are 100% factory. One is 11.5" BCM ELW barrel, other is Larue 12.5" Ultimate upper (Stealth barrel). Ejection on both is closer to 3:00 but brass appears fine. Although I didn't look too close.

[Casual Friday]

Both uppers are 100% factory. One is 11.5" BCM ELW barrel, other is Larue 12.5" Ultimate upper (Stealth barrel). Ejection on both is closer to 3:00 but brass appears fine. Although I didn't look too close.

I can't speak to the LaRue upper, but up until a month or two ago I had a BCM 11.5" ELW. I ran it with the A5H2 buffer and it ran very well and was quite smooth. The gas port was .073".

[TGS]

Both uppers are 100% factory. One is 11.5" BCM ELW barrel, other is Larue 12.5" Ultimate upper (Stealth barrel). Ejection on both is closer to 3:00 but brass appears fine. Although I didn't look too close.

Oh ok, yeah, that's more of what I would think. By common convention, your rifle "should" get at least an H buffer.

Unless someone pipes up with some data from an armorers course that 3 O'Clock ejection is proven to result in an X-percentage lower bolt life, I think it's a fairly academic "should", though. I'd probably do it (H, H2 or A5) just because I'm a geek and would want it smoother, anyway. I don't think it's anything to worry about IMO, though.

[Shawn Dodson]

I experiment with heavier buffer springs first then experiment with heavier buffers. A heavier spring (e.g., Sprinco blue or Sprinco red) performs the same function as a heavier buffer but without adding reciprocating weight, which causes muzzle jump. I have carbine standard, Sprinco blue and Sprinco red springs and standard carbine, H, H2 and H3 buffers. I experiment by trying different combinations of spring weights and buffer weights and determining which combination works best in controlling muzzle jump while maintaining reliable functioning.

Spent case ejection angle can be be affected by the BCG finish. I've had NiB BCGs eject at 1 o'clock that when swapped with a phosphate BCG in the same gun change ejection angle to 4 o'clock. Similar situation with BCG lube. A phosphate BCG that reliably ejected to 4 o'clock with one lube suddenly starts ejecting to 1 o'clock with Cherry Balmz Black Rifle Balm.

[MistWolf]

Bottom line- Carbine buffers are too light. They give sharper than necessary recoil even when an AR is properly gassed, giving the shooter the impression the AR is over gassed. An AR with a carbine buffer isn't over gassed, it's under buffered.

The standard buffer for an issue M4 is the H2. The standard buffer for a Colt civilian 6920 is an H.

The H3 is the same weight as a rifle buffer and an A5H2, but things start getting out of balance with an H3 because you're stuck using a carbine length spring. It's better to switch to an A5 or rifle setup at that point, to gain the advantage of the longer length of the rifle spring.

[Wonder9]

Buffer weight is pointless on a semi-auto AR.

[MistWolf]

Buffer weight is pointless on a semi-auto AR.

After experimenting with various buffers & gas settings, I must disagree.

[Casual Friday]

Buffer weight is pointless on a semi-auto AR.

You'll have to sell that kind of bullshit in a Facebook gun group. We ain't buyin'.

[Elwin]

I'm fairly clueless with rifles and know it. So what I did for my 16" Mid BCM upper was look up BCM's specs for their complete 16" midlength rifles and copy that, at least as a starting point (happens to be an H buffer and a presumably mil-spec spring). You could probably do the same, again at least as a place to start.

(Edited typo)

[Rex G]

Interesting discussion. I was contemplating using more than one upper, on a lower, as I recently added several uppers, so have more completed uppers than completed lowers, at this time.

[Wonder9]

You'll have to sell that kind of bullshit in a Facebook gun group. We ain't buyin'.

Whoever pissed in your Cheerios this morning swiped your manners too.

FACT: Since the XM177, the CAR buffer was standard until the Colt 920. Over 30 years of Colt carbine models from the XM177 to the 723/733 never had an issue with a CAR buffer.

FACT: The M4 Program introduced the H buffer and M4 feedramps to fix feed issues in full auto. Colt fixed the issues with either the feedramps or the H buffer, leaving a redundancy. The feed issues were all under full auto conditions, there was NOT an issue in semi-auto only with the M4 Carbine.

FACT: M4A1 received the H2 buffer after issues due to full auto and the heavier barrel profile. Once again, there was NO issues in semi-auto with the M4A1.

FACT: H3 buffers were designed for the Colt IAR. There were NEVER designed for a DI AR-15, only a meme piston AR.

Now, last I checked, there ain't a COTS AR-15 with a happy switch. There is NO need for a heavy buffer on a semi-auto only AR15. There were not engineered because you have an under/over gassed AR or there was a problem with the CAR buffer.

[Wonder9]

After experimenting with various buffers & gas settings, I must disagree.

I have never seen a problem that was directly related to the buffer. I will agree you can smooth up the recoil impulse with a heavier buffer, but I will retain that it is not needed for proper function.

There is a problematic issue in the AR world that can be viewed in this very forum. People get an AR and start changing shit before they even fire it because Brand Y is shit, you need Brand X widget to make a M4gery not fall apart in your hands. Let alone people with functional AR-15s that read forums and buy into the marketing side instead of 60 years of government development and actually shooting their functional AR-15. It's not an firearm issue, but marketing bullshit that can be found in motor vehicles, guitars, and anything else where the tangible goods can last for lifetimes.

[Casual Friday]

Whoever pissed in your Cheerios this morning swiped your manners too.

FACT: Since the XM177, the CAR buffer was standard until the Colt 920. Over 30 years of Colt carbine models from the XM177 to the 723/733 never had an issue with a CAR buffer.

FACT: The M4 Program introduced the H buffer and M4 feedramps to fix feed issues in full auto. Colt fixed the issues with either the feedramps or the H buffer, leaving a redundancy. The feed issues were all under full auto conditions, there was NOT an issue in semi-auto only with the M4 Carbine.

FACT: M4A1 received the H2 buffer after issues due to full auto and the heavier barrel profile. Once again, there was NO issues in semi-auto with the M4A1.

FACT: H3 buffers were designed for the Colt IAR. There were NEVER designed for a DI AR-15, only a meme piston AR.

Now, last I checked, there ain't a COTS AR-15 with a happy switch. There is NO need for a heavy buffer on a semi-auto only AR15. There were not engineered because you have an under/over gassed AR or there was a problem with the CAR buffer.

Cool story bro. In 2020, what reputable AR manufacturers are using carbine buffers? By reputable I don't mean PSA, Spikes, or Anderson.

[Casual Friday]

I have never seen a problem that was directly related to the buffer. I will agree you can smooth up the recoil impulse with a heavier buffer, but I will retain that it is not needed for proper function.

There is a problematic issue in the AR world that can be viewed in this very forum. People get an AR and start changing shit before they even fire it because Brand Y is shit, you need Brand X widget to make a M4gery not fall apart in your hands. Let alone people with functional AR-15s that read forums and buy into the marketing side instead of 60 years of government development and actually shooting their functional AR-15. It's not an firearm issue, but marketing bullshit that can be found in motor vehicles, guitars, and anything else where the tangible goods can last for lifetimes.

That is a pretty bold statement to make considering the vast majority of PF members are shooters and base their suggestions on personal experience.

[Wonder9]

Cool story bro. In 2020, what reputable AR manufacturers are using carbine buffers? By reputable I don't mean PSA, Spikes, or Anderson.

Do you have a retort on the history and engineering of the CAR buffer? Because I just read some Facebook gun group horseshit response "BRAND X DOESN'T USE IT SO IT'S SHIT".

The H and H2 buffers were created to fix issues due to fully automatic fire in the 920 series. That is historical fact without emotion.

[Casual Friday]

Do you have a retort on the history and engineering of the CAR buffer? Because I just read some Facebook gun group horseshit response "BRAND X DOESN'T USE IT SO IT'S SHIT".

The H and H2 buffers were created to fix issues due to fully automatic fire in the 920 series. That is historical fact without emotion.

Who said anything about doubting the origins? I'm talking about real world application in 2020, or even the last decade. What reputable manufacturers supply their rifles with carbine buffers?

[Wonder9]

That is a pretty bold statement to make considering the vast majority of PF members are shooters and base their suggestions on personal experience.

And my personal experience is people want to swap parts before they even vet what they have because they read it on the internet. Open nearly any "My new Glock is malfunctioning" thread and it's because it's all aftermarket parts. Just like I'm sure there was a respected PF member that probably recommended a BAD lever.

[Casual Friday]

And my personal experience is people want to swap parts before they even vet what they have because they read it on the internet. Open nearly any "My new Glock is malfunctioning" thread and it's because it's all aftermarket parts. Just like I'm sure there was a respected PF member that probably recommended a BAD lever.

That almost never happens on PF.

[Wonder9]

Who said anything about doubting the origins? I'm talking about real world application in 2020, or even the last decade. What reputable manufacturers supply their rifles with carbine buffers?

BRO, WHY DO MANUFACTURERS FOLLOW TDP AND ECONOMY OF SCALE?

You are taking the discussion on a tangent that does not follow my statement. My argument is any properly-built AR-15 carbine can use a CAR buffer. The heavy buffers were designed for automatic fire issues and the only AR carbines that truly benefit from an H would be an upper without M4 feedramps.

[Wonder9]

That almost never happens on PF.

Almost is the key word. PF is an awesome site with awesome shooters, but we are all human.

Regardless, I'll still stand by my point that buffer weights are largely pointless on an AR-15 carbine due to it being semi-auto only. I would concede that they are requirements if you have a select fire M4 or M4A1.

[Wake27]

I’ve been running my AR pistols (all with 11.5-12.5” barrels) with carbine buffers, and zero problems. Other than shooting softer, is there a reason to start fiddling around with other buffers? Again, I’ve had no reliability issues whatsoever, so if ain’t broke...

I also make it a point to shoot 5.56 (not .223) and generally avoid cheap ammo if that matters.

I skimmed the SBR/pistol thread and didn’t see this addressed directly.


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I’d go heavier. I’ve experimented a fair amount and really haven’t noticed too much difference honestly so I just like to be somewhere in the middle. CAR and H3 are on opposite ends just as A5H0 and A5H4 are so I like somewhere around the H-H2 or A5H2-A5H3. The only thing I can say for certain is that changing springs and changing buffers is not the same thing. They’re obviously related but putting in a green spring and A5H1 is not the same thing as a standard rifle spring and A5H2.

Realistically the recommendation of whatever your upper’s manufacturer recommends is probably the best one, seeing as how you have solid uppers. They’ll probably recommend a light buffer anyways since they want their guns to run but I’d be surprised if BCM didn’t use at least an H buffer in their 11.5s.

On the emotional argument about necessity, it’s the same as always. Colt 6920 works so it’s fine, but KAC SR-15 is going to be better. Just depends if you want to spend the money and accept whatever risk there is from diverting from “fine.” In this instance, it’s not even $50 unless you start toying with the A5 system, is easy to put back to how it was if it doesn’t work, and assuming you’re able to test it enough to feel confident in it, there’s really not a downside.

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[Casual Friday]

BRO, WHY DO MANUFACTURERS FOLLOW TDP AND ECONOMY OF SCALE?

You are taking the discussion on a tangent that does not follow my statement. My argument is any properly-built AR-15 carbine can use a CAR buffer. The heavy buffers were designed for automatic fire issues and the only AR carbines that truly benefit from an H would be an upper without M4 feedramps.

Who said a properly built AR15 wouldn't run with a carbine buffer? Nobody in this thread. You said
Buffer weight is pointless on a semi-auto AR. That's an incredibly foolish statement. If you'd said they weren't necessary for function, that would be a different story. My rifles, factory built or by me, from reputable manufacturers will all run on a carbine buffer. They run smoother with heavier buffers. To say anything other than a carbine buffer is pointless is borderline fudd lore similar to .45acp stoppin powah.

Colt, BCM, Daniel Defense, SOLGW, Geissele, LMT, all use H or heavier buffers. Are they wrong? What do you know that they don't?

[rd62]

Except the OP wasn't talking about 14-16" CAR rifles but 11.5-12.5 pistol/SBR setups with shorter dwell times. It'll certainly run with a CAR buffer but it may not be ideal.

[DpdG]

Whoever pissed in your Cheerios this morning swiped your manners too.

FACT: Since the XM177, the CAR buffer was standard until the Colt 920. Over 30 years of Colt carbine models from the XM177 to the 723/733 never had an issue with a CAR buffer.

FACT: The M4 Program introduced the H buffer and M4 feedramps to fix feed issues in full auto. Colt fixed the issues with either the feedramps or the H buffer, leaving a redundancy. The feed issues were all under full auto conditions, there was NOT an issue in semi-auto only with the M4 Carbine.

FACT: M4A1 received the H2 buffer after issues due to full auto and the heavier barrel profile. Once again, there was NO issues in semi-auto with the M4A1.

FACT: H3 buffers were designed for the Colt IAR. There were NEVER designed for a DI AR-15, only a meme piston AR.

Now, last I checked, there ain't a COTS AR-15 with a happy switch. There is NO need for a heavy buffer on a semi-auto only AR15. There were not engineered because you have an under/over gassed AR or there was a problem with the CAR buffer.


I don't think many would dispute these facts, but speaking of buffer weights alone without the relationship to gas port sizing is myopic. Colt controlled the entire gun and varied gas port sizing for each application. I believe once you leave the Colt world, you'll see a bunch of different port sizes across different brands, even for the same barrel length/gas system. If the gas port is on the bigger or smaller size for the application, buffer weight can be used to fine tune the system for best function and parts reliability.

I've heard "for semi- as long as it runs, buffer weight doesn't matter." I don't entirely disagree, but too much gas/too little buffer is a) hard on trigger pins, and b) more recoil impulse than necessary. What's the harm in trying different buffer weights in that situation?

[Wonder9]

Except the OP wasn't talking about 14-16" CAR rifles but 11.5-12.5 pistol/SBR setups with shorter dwell times. It'll certainly run with a CAR buffer but it may not be ideal.

You mean like the XM177/GAU-5A and 733 Commando? ;)

[Wonder9]

I've heard "for semi- as long as it runs, buffer weight doesn't matter." I don't entirely disagree, but too much gas/too little buffer is a) hard on trigger pins, and b) more recoil impulse than necessary. What's the harm in trying different buffer weights in that situation?

There is no harm, but advising throwing in heavy buffers because "ONLY THE MOST ELITE COMPANIES EQUIP THEIR AR-15s WITH H BUFFERS" is mindless consumer thinking. My original point is that Darth_Uno does not need to fuck with the buffer on a functioning rifle. The buffer is in spec and heavy buffers were never designed to smooth up the action, but to fix issues that only occur in select-fire..... with black follower USGI magazines and M855.

I would also argue that severely overgassed carbines would benefit for a adjustable gas block or BRT gas tube helluva more than a buffer.

[Casual Friday]

There is no harm, but advising throwing in heavy buffers because "ONLY THE MOST ELITE COMPANIES EQUIP THEIR AR-15s WITH H BUFFERS" is mindless consumer thinking. My original point is that Darth_Uno does not need to fuck with the buffer on a functioning rifle. The buffer is in spec and heavy buffers were never designed to smooth up the action, but to fix issues that only occur in select-fire..... with black follower USGI magazines and M855.

I would also argue that severely overgassed carbines would benefit for a adjustable gas block or BRT gas tube helluva more than a buffer.

You do realize that Colt, the company you keep bringing up, doesn't ship their rifles with carbine buffers, right? And they haven't for a long time. Are they wrong? What do you know that Colt doesn't?

[MistWolf]

I have never seen a problem that was directly related to the buffer. I will agree you can smooth up the recoil impulse with a heavier buffer, but I will retain that it is not needed for proper function.
Define proper function. Will go bang every time and cycle? Certainly. But the system will be out of balance and it's timing off.


There is a problematic issue in the AR world that can be viewed in this very forum. People get an AR and start changing shit before they even fire it because Brand Y is shit, you need Brand X widget to make a M4gery not fall apart in your hands.
This is irrelevant to the discussion. No one in this thread is changing out parts before before shooting or even suggesting it. The suggestion is to change out a substandard part (carbine weight buffer) for the right part. I have personally shot an AR enough to verify a carbine weight buffer is substandard.


Let alone people with functional AR-15s that read forums and buy into the marketing side instead of 60 years of government development and actually shooting their functional AR-15.
H and H2 buffers are not marketing hype. The H (and later the H2 buffer) were developed because the carbine buffer was too light and bolt bounce was a problem, a problem that was revealed during full auto fire. The heavier buffers solved the bolt bounce problem by smoothing out the action. Note that buffers with floating weights were developed for the same reason. The rifle, H and H2 buffers are the result of 60 years of shooting and development by the government.


BRO, WHY DO MANUFACTURERS FOLLOW TDP AND ECONOMY OF SCALE?
I won't go into the legal reasons why many makers of ARs do not follow the TDP, but I will point out that the carbine weight buffer doesn't follow the TDP for the M4 or M4A1


My argument is any properly-built AR-15 carbine can use a CAR buffer. The heavy buffers were designed for automatic fire issues and the only AR carbines that truly benefit from an H would be an upper without M4 feedramps.
It's also true that any properly built AR carbine can use an over sized gas port. In fact, some very knowledgeable folks argue that an over gassed AR is preferable for more reliable extraction. But it does put the system out of balance and throws off the timing.

The claim that the only ARs that can benefit from from an H buffer is an upper without M4 ramps ignores the fact that even with the proper size gas port, with carbine buffers extraction is more violent, placing greater strain on the extractor. It ignores the fact that recoil is sharper (not increased). Sharper recoil requires more work for the shooter and increases shooter fatigue.


You mean like the XM177/GAU-5A and 733 Commando? ;)
The XM177 series was popular in spite of its lack of refinement.


There is no harm, but advising throwing in heavy buffers because "ONLY THE MOST ELITE COMPANIES EQUIP THEIR AR-15s WITH H BUFFERS" is mindless consumer thinking.
No, it's based on experience shooting and experimenting with different uppers & lowers


My original point is that Darth_Uno does not need to fuck with the buffer on a functioning rifle. The buffer is in spec and heavy buffers were never designed to smooth up the action, but to fix issues that only occur in select-fire..... with black follower USGI magazines and M855.
Carbine buffers are not within spec. They are obsolete and the carbines delivered to the military do not use them. M4s & M4A1s are delivered with H2 buffers.

The H and H2 buffers were indeed developed to smooth the the function of short ARs. With the carbine weight buffers, they discovered that bolt bounce caused malfunctions during autofire. Buffers needed heavier floating weights to smooth out function and eliminate bolt bounce. The results was a better weapon in both semiauto and full auto fire.


I would also argue that severely overgassed carbines would benefit for a adjustable gas block or BRT gas tube helluva more than a buffer.
You almost got this right. Proper gas drive is very important. Over gassing cannot be fixed with a heavier buffer. It must be fixed by controlling the flow, ideally by the right diameter gas port, but an adjustable gas block or one of Clints EZ tune gas tubes are just as effective.

It's accepted that a 20 inch AR with its rifle length gas system and rifle buffer is well balanced and sets the standard for reliability and durability. As I recall, military testing has proven this out. ARs with shorter gas systems have a more violent operating cycling due largely to the increased gas pressure used to drive it. This has been exacerbated by using a lighter buffer and shorter spring to achieve the shortest weapon possible. A carbine buffer weighs about 3.0 ozs. A rifle buffer weighs about 5.2 ozs and gives smoother function regardless of barrel & gas system length than a carbine weight buffer. Semiauto ARs certainly do benefit from using H/H2/A5H2/rifle buffers over carbine buffers.

[ViniVidivici]

Excellent post Mr. Wolf. That should be tacked somewhere.

I'm running H2 in everything now, from 18" to my shorty 11.5". I've found it's the sweet spot.

My shorty ran just fine with carbine, but runs smoother, and is less jumpy with H2.

[RAM Engineer]

I run H2 in my Elmore 14.5" and H3 in my Elmore 10.3". Both, per his direction.

[RancidSumo]

Hijacking this thread for a related question.

Where should I start with the spring/buffer combo on a 7" 300BO? I put in the standard Sprinco Blue/H2 to start with, but it won't cycle subs. I played with the gas block some at the range, but before going crazy with that I figured I should make sure I'm starting from the right place. Gun is currently unsuppressed but eventually it will be suppressed full time.

I also have on hand buffers from carbine to H2 and a standard carbine spring or Sprinco Hot White.

[MistWolf]

Hijacking this thread for a related question.

Where should I start with the spring/buffer combo on a 7" 300BO? I put in the standard Sprinco Blue/H2 to start with, but it won't cycle subs. I played with the gas block some at the range, but before going crazy with that I figured I should make sure I'm starting from the right place. Gun is currently unsuppressed but eventually it will be suppressed full time.

I also have on hand buffers from carbine to H2 and a standard carbine spring or Sprinco Hot White.

Your AR is under-gassed. You ain't gonna fix under-gassing with buffers or springs. Either add a suppressor (which increases back pressure by increasing blow down time) or open up the gas port in the barrel.

[RancidSumo]

Your AR is under-gassed. You ain't gonna fix under-gassing with buffers or springs. Either add a suppressor (which increases back pressure by increasing blow down time) or open up the gas port in the barrel.

It has an adjustable gas block with plenty of room to open up still, so I'm sure I can get there, just thought I should start from the right place with the buffer/spring before adjusting the gas to get it right.

[Norville]

It has an adjustable gas block with plenty of room to open up still, so I'm sure I can get there, just thought I should start from the right place with the buffer/spring before adjusting the gas to get it right.


You probably know this, but getting a gun to cycle both supers and subs often requires a gas setting change, especially if a suppressor adds another variable. Set it up to run your preferred combination, theN see what changes might be needed to run with alternate configurations.