Current LE 10.5 M4 Carbines

[SW CQB 45]

I was asked to find some Colt M4 Commandos for our Moto Officers to be mounted in the HD saddlebags in a ProGuard lock.

I looked up the specs for the ProGuard mount and it specifies "Fits Colt “Commando” M4 Carbine or variant (maximum 27¼” overall weapon length with stock collapsed)"

It appears Colt Commando may be difficult to find, and they have an 11.5 barrel which may take them over the max length.

I looked at the FN 11.5 SRP and its min overall length is 27.5"

I need to find a 10.5" M4 that can be purchased through an outlet to be an approved vendor (City Govt Rules) with a max collapsed length of 27.25".

Are 10.5" Colts still available? Model #?
any 10.5" variants that I can look at of quality manufacture (no PSA or pieced together)

buying 16" M4 carbine gas length is not out of the question if I have to switch to a 10.5 barrel and heavier buffer.

I am sorry if this is common knowledge, I got transferred back to Patrol a few years ago and busier than ever. Workload and handguns (ha!) and I lost track with the M4 platforms and what is currently available.

thanks in advance

[HCM]

I was asked to find some Colt M4 Commandos for our Moto Officers to be mounted in the HD saddlebags in a ProGuard lock.

I looked up the specs for the ProGuard mount and it specifies "Fits Colt “Commando” M4 Carbine or variant (maximum 27¼” overall weapon length with stock collapsed)"

It appears Colt Commando may be difficult to find, and they have an 11.5 barrel which may take them over the max length.

I looked at the FN 11.5 SRP and its min overall length is 27.5"

I need to find a 10.5" M4 that can be purchased through an outlet to be an approved vendor (City Govt Rules) with a max collapsed length of 27.25".

Are 10.5" Colts still available? Model #?
any 10.5" variants that I can look at of quality manufacture (no PSA or pieced together)

I am sorry if this is common knowledge, I got transferred back to Patrol a few years ago and busier than ever. Workload and handguns (ha!) and I lost track with the M4 platforms and what is currently available.

thanks in advance

Most LE running SBR's are running 11.5" guns for reliability and durability reasons. There's a reason nearly all Fed LE (FBI, ICE, CBP/USBP, USSS, etc) running SBRs are running 11.5". The only one I'm aware of running 10.5" guns is Dept of State running Mk18's.

TGS

Prior to the Navy asking for the Mk18 Colt refused to make AR's shorter than 11.5" AFAIK Colt doesn't offer a 10.5" for commercial/LE sales.

If I had to have a 10.5"/10.3" DI gun for duty I would be looking at Daniel Defense, maybe Geissele, BCM or Son of Liberty Gunworks.

Sub 11.5" is one instance where it might be worth looking at piston guns since it eliminates the dwell time issue. The HK 416 and LWRC's are available as 10-ish inch guns.

[SW CQB 45]

this was spec by our SWAT Commander some years ago (I guess when 10.5) was everywhere and 11.5 was the new guy on the block,

LE6945CQB which are actually 10.3"

11.5" barrels are to long for the Harley bags and Pro Guard mounts.

thanks for the info. I will check into those.

[rd62]

My 10.5" LMT has been tits.

May be worth a look.

[JclInAtx]

Arms unlimited lists the le6945cqb in stock https://www.armsunlimited.com/Colt-556mm-Semi-Auto-10-3-Barrel-CQB-Rifle-p/le6945cqb.htm

[SW CQB 45]

Checking websites, 11.5 has taken over for 5.56.

LMT has a 10.5 with an overall length of 26" and I left a message with their LE Dept to call me.

thanks

[Default.mp3]

Interestingly, the website itself says it'll fit up to 27.5", which would give you a lot more options since the 11.5" rifles would be available. Obviously, this contradicts their published spec sheet, which they link in said website. Might be worth reaching out to Pro-gard and double checking to see which number is right, given the advantages of the 11.5".

[SW CQB 45]

Interestingly, the website itself says it'll fit up to 27.5", which would give you a lot more options since the 11.5" rifles would be available. Obviously, this contradicts their published spec sheet, which they link in said website. Might be worth reaching out to Pro-gard and double checking to see which number is right, given the advantages of the 11.5".

great idea

I thought max length on the ProGuard website was 27.25"

[theJanitor]

Can you retrofit a LAW folder later? A factory BCM 12.5 and a LAW would be a sweet combo

[SW CQB 45]

Can you retrofit a LAW folder later? A factory BCM 12.5 and a LAW would be a sweet combo

I thought about that too and I agree with that set up.

My current issue is a 12.5 BCM upper on a Colt SP1 lower.

The lower was likely evidence many moons ago (before my time) as its machined to a full auto. It's registered to the dept, but when I found it on SWAT it had a horrible fit 16" barrel and semi auto trigger. I told Admin that somehow through the years, the stuff that was supposed to be on there walked off. They allowed me to return it what it should be.

I took off the full auto trigger (stored in a locked cabinet) as everyone wanted to dump a mag but the trigger press was not that great. The hammer pin holes were starting to get oblong. I put a ALG trigger and those contraptions to secure the trigger and hammer pins and all is well.

[SeriousStudent]

Can you retrofit a LAW folder later? A factory BCM 12.5 and a LAW would be a sweet combo

Indeed it is. I have one.

[HCM]

this was spec by our SWAT Commander some years ago (I guess when 10.5) was everywhere and 11.5 was the new guy on the block,

LE6945CQB which are actually 10.3"

11.5" barrels are to long for the Harley bags and Pro Guard mounts.

thanks for the info. I will check into those.

For clarity, 11.5" was the standard via Colt (as the "Commando) for decades, not the new guy on the block. Colt refused to make sub 11.5" factory guns until the Navy put out the requirement for the Mk18.

Early in the GWOT a lot of "cool guy" units wanted or needed guns shorter than 14.5" and went to the MK18 because it was available "in the system." Suffice to say 10.5" guns, suppressed, full auto had reliability and durability service life issues. This lead the coolest of GWOT cool guys to 10.5" piston guns in the form of the HK416.

Outsiders looking in made 10.5" the hotness but were either unaware of or willfully blind to the downsides.

Semi auto, unsuppressed, a good factory 10.5" DI gun like a DD or LMT will run but the life of things like the action spring and bolt will be much shorter. There's no free lunch.

[TGS]

Semi auto, unsuppressed, a good factory 10.5" DI gun like a DD or LMT will run but the life of things like the action spring and bolt will be much shorter. There's no free lunch.

What's the expected bolt life on an 11.5" gun?

[Paul Blackburn]

SOLGW does 10.5's and has a lot of LE contracts.

Their guns are awesome and he does the armorer courses for LE so they know hoe to maintain them properly.

[HCM]

What's the expected bolt life on an 11.5" gun?

Book answer for PMCS- 12k vs 7 or 8k on a 10.5” - 14.5” or 16” should be 15k - 20” rifles are usually good for 20k.

All of that assumes a properly gassed carbine length gas system (or rifle gas in the case of the 20”

An over gassed system will be less, as much as 1/3 less. Along those lines, firing schedule will make a difference, not just round count and increased gas via back pressure from suppressed fire will accelerate bolt wear as well.

Hence why I would stick with DD or LMT for a DI 10.5”

[HCM]

SOLGW does 10.5's and has a lot of LE contracts.

Their guns are awesome and he does the armorer courses for LE so they know hoe to maintain them properly.

SOLGW has some LE contracts. They are very knowledgeable, knowledgeable enough that they will normally try to talk LE customers out of going with a 10.5 for duty use and suggest an 11.5 or 12.5 instead.

For the OP, they SOLGW makes duty grade guns on par with Colt and BCM and they are TX based if that makes a difference to your purchasing people.

[Paul Blackburn]

Book answer for PMCS- 12k vs 7 or 8k on a 10.5” - 14.5” or 16” should be 15k - 20” rifles are usually good for 20k.

All of that assumes a properly gassed carbine length gas system (or rifle gas in the case of the 20”

An over gassed system will be less, as much as 1/3 less. Along those lines, firing schedule will make a difference, not just round count and increased gas via back pressure from suppressed fire will accelerate bolt wear as well.

Hence why I would stick with DD or LMT for a DI 10.5”

What is PMCS?

[HCM]

What is PMCS?

Preventive Maintenance Checks / Services.

Includes things like proactively replacing high wear parts and springs before they break, deep cleaning to allow a detailed examination looking for unusual wear patterns or cracks, gauging things like bore/throat erosion, checking headspace etc.

[Paul Blackburn]

SOLGW has some LE contracts. They are very knowledgeable, knowledgeable enough that they will normally try to talk LE customers out of going with a 10.5 for duty use and suggest an 11.5 or 12.5 instead.

For the OP, they SOLGW makes duty grade guns on par with Colt and BCM and they are TX based if that makes a difference to your purchasing people.

Mike Mihalski definitely know the AR platform through and through, from metallurgy, destructive testing, data, QC, to trivial details. His Armorer courses are excellent and the carbines are quality and durable.

[HCM]

Mike Mihalski definitely know the AR platform through and through, from metallurgy, destructive testing, data, QC, to trivial details. His Armorer courses are excellent and the carbines are quality and durable.

SOLGW is local, I’ve known those guys (including Mike) long before they were doing armorers courses or were Instagram famous.

They (not just Mike) know the AR platform quite well.

[Gray Ghost]

I have an LMT 10.5" upper that I bought in about 2003. It has always run like a sewing machine with a standard buffer. I have often run it suppressed with a Gemtech HALO can I bought about the same time. That said it probably has less than 3k rounds on it. I am promiscuous about owning and shooting other guns, and I don't have the training tempo of the cool guys. I doubt the motorcycle officers in question do either.

I also have a complete DD factory Mk18 that I bought in 2020. It runs very smoothly, and I would not hesitate to recommend it. I bought it as a braced pistol, but I think I am going to eFile a Form 1 this weekend to make it an SBR.

[BWT]

I think people identify with their barrel length too heavily.

Re-reading the posts the only thing that could be a negative light is folks are saying it wears faster and relayed data.

Nobody is saying your DD or LMT are bad - but it does wear faster with a shorter barrel length. Just adjust your maintenance interval and expectations and drive on.

https://danieldefense.com/barrels/11-5-inch.html

https://lmtdefense.com/product/11-5-5-56-nato/

DD and LMT both offer 11.5” barreled AR’s. Even the new HK’s are 11.5”.

https://www.heckler-koch.com/en/products/military/assault-rifles/hk416-a5/hk416-a5-11/overview.html

I just don’t get it. Anyway, I’ll shut up and go back to my corner.

[ASH556]

I bought my 10.3 DD MK18 as a Form 4 gun in 2011. I ditched the DD barrel about the time I got my suppressor and went to a Colt. I've had 2 barrels in the gun that were Colt SOCOM's cut to 10.3 by ADCO. Various reasons around switching configurations and trying new things sent both those barrels down the river. In both cases I had ADCO port them at .070 when they did the cut and thread. Currently I have a Colt factory 10.3 in the gun with a verified .070 gas port. All of these have run 100% suppressed and un-suppressed using a Colt factory action spring and H2 buffer (actually it's the DD factory "H" buffer, but I swapped a steel weight for tungsten. I mostly shoot .223 pressure ammo for practice as my go-to ammo is .223 pressure 62gr Speer Gold Dot. That said, I have fired 5.56 pressure M193 and M855 ammo with no issues.

Total round count across all of these combined is probably in the 4K-5K range with probably 40-50% suppressed. If I'm shooting a match or doing range work with others without suppressors, I see no reason to put the wear on mine.

The one place I have observed real "premature" wear is in the action spring. Now, I'm only going by spring length as that's what's prescribed in the TM and what was taught to me by Will Larson. Theoretically you could somehow measure spring output force across compression and come up with a real "life" measure, but I'm not equipped to do that. Action springs are below their min length at about 1,500 rds. I did recently add another tungsten weight to my buffer, thus making it an H3 to hopefully solve this issue.

I measure the effectiveness of this in the fact that it's slowed the bolt speed enough for 20rd Colt mags, which used to have issues in this gun, no longer do. 30rd Pmags, which are my go-to, have always been fine.

[SLUZENE]

11.5" upper with a lower with the LWRCI UCIW Stock Kit? https://www.lwrci.com/LWRCI-UCIW-Stock-Kit-_p_38.html

[SW CQB 45]

Since the concept of this post was the "shorty" needed to fit in a Harley Police Bike hard bag and the maker of the gun lock said a Commando 10.5.

What we found out through another PD.... an 11.5 will work with mods to the bag.

Worst case scenario, we can add a folder or mod a stock or get one of those fancy short stocks before we would grind on a Harley bag.

With this info, the options OPEN UP!

I am not sure what Admin :l will approve.

thanks everyone.

[andre3k]

Since the concept of this post was the "shorty" needed to fit in a Harley Police Bike hard bag and the maker of the gun lock said a Commando 10.5.

What we found out through another PD.... an 11.5 will work with mods to the bag.

Worst case scenario, we can add a folder or mod a stock or get one of those fancy short stocks before we would grind on a Harley bag.

With this info, the options OPEN UP!

I am not sure what Admin :l will approve.

thanks everyone.Harley guys have it easy. Try getting any SBR to fit into the trunk of a Goldwing.

Sent from my SM-G965U using Tapatalk

[HCM]

Since the concept of this post was the "shorty" needed to fit in a Harley Police Bike hard bag and the maker of the gun lock said a Commando 10.5.

What we found out through another PD.... an 11.5 will work with mods to the bag.

Worst case scenario, we can add a folder or mod a stock or get one of those fancy short stocks before we would grind on a Harley bag.

With this info, the options OPEN UP!

I am not sure what Admin :l will approve.

thanks everyone.

If the bags are full enclosed the LAW folder is an option (if not too thick folded.

The LWRC compact stock kit takes an inch off the OAL. Depending on how your bags are configured it might allow y’all to run 11.5”

https://www.lwrci.com/LWRCI-UCIW-Stock-Kit-_p_38.html

[Default.mp3]

The LMT PDW lower also lops off 3" allegedly, might be worth a gander. At that rate, you could potentially fit a 12.5" in there (OAL would be 26.5"). Maxim Defense also has some options that would lop off length, though that would be still only be a 10.5", so meh.

[jc000]

OP, if you're looking at other options, Sionics Weapons Systems does a lot of work with LE and have an 11.5" option (https://sionicsweaponsystems.com/lawenforcement/sionics-11-5-upper-receiver-group-premium-edition/). I own a 16" and have been extremely pleased with reliability, accuracy, and their customer service.