Newby Guide to Suppressor on ARs

[wind gypsy]

My main home defense/SHTF gun is a 14.5" BCM that I had a TBAC cb flash hider tacked to avoid NFA and make compatible with my ultra 7.

After just a little shooting with the can (maybe 100-150 rounds?) I was amazed at how filthy the rifle got and wasn't a big fan of some of the blowback. I'm AR ignorant but know there are adjustable gas blocks and certain cans designed to supposedly minimize backpressure that may help but I've no idea if that stuff is worth pursuing. I freaking hate cleaning rifles and the sight of carbon caking everything after minimal firing resulted in me taking the can off the rifle for now. Questions:

1. Is this basically to be expected or can a guy take some measures to avoid the gun getting so filthy and reduce blow back? Reliability is paramount and this rifle runs like a top compared to my DPMS and RRA ARs and i don't want to do anything that could change that.
2. How much should a guy worry about the mess created and what cleaning regimens are reasonable to ensure reliability isn't impacted?

 

[SloppyJ]

I think you have a two part approach as long as you can live with the fact that shooting a gas gun suppressed is going to be dirtier. Period.

First, look into some of the mitigation measures that you mentioned. Personally, I've had great luck with the Superlative Arms adjustable gas block. It has a blow off feature that seems to make a bit of difference. There are certainly cans that are better than others when it comes to backpressure but I'm not sure it's that much of a difference. Supposedly, the Huxwrx flow series is the best flow through technology at this time. Although there is another company releasing very soon with similar claims. I've shot an Huxwrx can (OSS before they rebranded) and still had some blow back. I didn't care for the sound either. I don't shoot a ton of 5.56 and it's probably one of the hardest rounds to suppress well so I personally wouldn't buy a dedicated 5.56 can unless I also shot a .223 hunting rifle.

The second is that I think you might be surprised on how dirty the gun can get before you start having reliability issues. The tolerances on AR rifles aren't as tight as the hunting guns that we use where some small amount of dirt or grime could keep you from chambering a round. I'd suggest you keep a round count and start doing some testing of where you start to see some sort of reliability drop offs. There's no doubt though, cleaning up after shooting suppressed sucks.

The last thing I'll mention is that you can also find some stuff for reducing the perceived blow back. Special charging handles, bolts, and all sorts of crap is out there. This won't make your gun cleaner, but it won't hit you in the face if that's another issue of yours.

Right now I mainly stick to .22lr and 300blk in AR platform. I have an M5 to build but I'm not motivated to start it. I load all of my own 300blk subs and supers so I'm able to tweak the load to what shoots best. I think that helps quite a bit too. Been having luck with 4227 with my 300blk sub loads. The one I do want to wrap up is my 9mm build which I think will be a really fun gun.

 

[wesfromky]

A lot of people run "flow through" cans on ARs to reduce the back pressure at possibly the expense of being a bit louder.

Here is a good overview of some of the changes you can make to the AR itself:

How to Build an AR-15 for Suppressors

Watch this engaging episode on How to Build an AR-15 & optimize it for silencers. Build a custom AR 15 for your next suppressor! Powered By Silencer Shop.

suppressorreadyfirearms.com

 

[matthewmt]

I have a couple bcm rifles by far my favorite. I rebarreled on recently to a rosco 14.5 mid length gas system with a pinned ASR 3 prong for the harvester evo.
I shot tikkas mainly with the suppressor and recently decided to try it on the 14.5. I don't recall gas port size from rosco but it is extremely pleasant as far as gas blow back gas in the face. A friend's bcm 16" mid length will draw tears every time.
With that being said I don't clean or lube my rifles hardly ever so I will have to do some inspection shortly.

Adjustable gas block may be worth investigating. I'm sure there are a number of quality ones on the market. I was told by a colt armorer with connections to well known builders and smith's who say that you want to tune a rifle to the suppressor and it should live on that gun but at any rate I'm willing to deal with some carbon should it build up.



Sent from my SM-G973U using Tapatalk

 

[hereinaz]

I run a YHM Nitro 30 on a QD brake. It’s dirty.

I too hate cleaning. Fortunately it’s easy to break down an AR and flush it out with a can of carb cleaner and compressed air. I use CLR or another carbon cleaner and soak the bolt carrier, sometimes ultrasound too. I try to do it more often to avoid build up. I don’t do a detailed OCD cleaning, just to knock the gunk back and keep it functionally clean.

It’s the price to pay for a suppressed AR, especially shorter barrels.

I am curious about the newer piston driven uppers. Brownells has one and if I remember PSA has one. I don’t keep up on them, but have seen them in emails I get. That makes me curious.

 

[Formidilosus]

My main home defense/SHTF gun is a 14.5" BCM that I had a TBAC cb flash hider tacked to avoid NFA and make compatible with my ultra 7.

After just a little shooting with the can (maybe 100-150 rounds?) I was amazed at how filthy the rifle got and wasn't a big fan of some of the blowback. I'm AR ignorant but know there are adjustable gas blocks and certain cans designed to supposedly minimize backpressure that may help but I've no idea if that stuff is worth pursuing. I freaking hate cleaning rifles and the sight of carbon caking everything after minimal firing resulted in me taking the can off the rifle for now. Questions:

Well first- stop cleaning and put the can back on. Yes your can is a high back pressure can and it is more of a challange to get that one working correctly with an AR than others, but it can be done. A low back pressure can will help. A Gas Buster charging handle of whatever brand/type will help a bit with gas to face.

1. Is this basically to be expected or can a guy take some measures to avoid the gun getting so filthy and reduce blow back? Reliability is paramount and this rifle runs like a top compared to my DPMS and RRA ARs and i don't want to do anything that could change that.

BCM’s are gassed pretty heavy. You can do all sorts of things to try to help it, but they are all bandaids. The simplest and probably most reliable way is to get a reduced sized gas tube from Black River Tactical. That’s and an H2 or H3 buffer would be my first steps.

2. How much should a guy worry about the mess created and what cleaning regimens are reasonable to ensure reliability isn't impacted?

Don’t clean. AR’s do not need to be clean to function perfectly, quite the opposite. Keep them lubed and you are good.

Over 40,000 rounds, 100% suppressed. 0 malfunctions.





Well over 60,000 rounds, 100% suppressed on the upper, no cleaning at all- 2 malfunctions caused by the firing pin retaining pin shearing off in the upper at about 40k rounds. No clue on the lower, it’s been in constant use since 2010- for reference this upper has only been in use since 2019.










I can show dozens more. AR’s do not need to be clean- they are filthy little hobbitses and they like it.

 

[hereinaz]

I can show dozens more. AR’s do not need to be clean- they are filthy little hobbitses and they like it.

Yikes!

Thank you good sir. Those pictures convince me. I am never cleaning my AR again…

 

[wind gypsy]

Well first- stop cleaning and put the can back on. Yes your can is a high back pressure can and it is more of a challange to get that one working correctly with an AR than others, but it can be done. A low back pressure can will help. A Gas Buster charging handle of whatever brand/type will help a bit with gas to face.





BCM’s are gassed pretty heavy. You can do all sorts of things to try to help it, but they are all bandaids. The simplest and probably most reliable way is to get a reduced sized gas tube from Black River Tactical. That’s and an H2 or H3 buffer would be my first steps.






Don’t clean. AR’s do not need to be clean to function perfectly, quite the opposite. Keep them lubed and you are good.

Over 40,000 rounds, 100% suppressed. 0 malfunctions.
View attachment 613442

View attachment 613443


Well over 60,000 rounds, 100% suppressed on the upper, no cleaning at all- 2 malfunctions caused by the firing pin retaining pin shearing off in the upper at about 40k rounds. No clue on the lower, it’s been in constant use since 2010- for reference this upper has only been in use since 2019.

View attachment 613444

View attachment 613445

View attachment 613446

View attachment 613447


I can show dozens more. AR’s do not need to be clean- they are filthy little hobbitses and they like it.

Thanks for the input. Those guns are nasty!

Do you a preferred upper assembly that is more ideal for use with suppressors?

Also - how do you lubricate them?

 

[NSI]

Pretty much what Form said.

1) Low back pressure can (I use HXWRX Flow 556k but Sig sLX and Griffin Eco work well).
2) Seal it up as best you can (I use the mini version of the Radian Raptor SD and do my best to keep my receiver halves tight)
3) Don't stress about cleaning, just lube.
4) Weigh your can. When it gains an ounce, soak it in CLR (or whatever your mfg suggests) overnight, shoot out the crap, and weigh it again.
5) Consider adjustable gas blocks like the Superlative with blow-by, heavier buffers, and other tuning measures if you must use a high-backpressure can. None of that gas is good for you or your performance.

Best,
-J

 

[Formidilosus]

Thanks for the input. Those guns are nasty!

Nasty guns are happy guns.

Do you a preferred upper assembly that is more ideal for use with suppressors?

No, not specifically for use with a suppressor. Well except DI and not pistons.
LMT mono uppers because of the total package- rail deflection, reliability, longevity, barrel change, etc., but I use lots of different ones. BCM makes a good rifle, though over gassed as mentioned. Hodge, KAC, Geissele, etc. Normal use carbines are 12.5” with mid length gas systems, or 14.5” with mid length gas. I shoot everything from 5.75” to 18” heavily, and in general the longest gas length that will function reliably gives the best performance and longevity.

Almost all barrels are over gassed due to the manufacturers being lazy and that is an easy way to get most guns to work, especially with weak 223 ammo.

In temps above the 20°’ish, a light coat of wheel bearing grease on all areas of the bolt carrier group will keep the rifle functioning very smoothly for about 500-700 rounds suppressed. You’ll feel it start to get sluggish when manually racking the charging handle, then just use a bit whatever liquid lube is handy (I have used olive oil, motor oil, vagisil, brake fluid, etc) on the CH, gas ports, a little on the bolt lugs, and a drop on the backside of the receiver behind the bolt and it will feel like silk. You can repeat the liquid lube thing every 500-700 rounds nearly indefinitely.

 

[bbell]

Well first- stop cleaning and put the can back on. Yes your can is a high back pressure can and it is more of a challange to get that one working correctly with an AR than others, but it can be done. A low back pressure can will help. A Gas Buster charging handle of whatever brand/type will help a bit with gas to face.





BCM’s are gassed pretty heavy. You can do all sorts of things to try to help it, but they are all bandaids. The simplest and probably most reliable way is to get a reduced sized gas tube from Black River Tactical. That’s and an H2 or H3 buffer would be my first steps.






Don’t clean. AR’s do not need to be clean to function perfectly, quite the opposite. Keep them lubed and you are good.

Over 40,000 rounds, 100% suppressed. 0 malfunctions.
View attachment 613442

View attachment 613443


Well over 60,000 rounds, 100% suppressed on the upper, no cleaning at all- 2 malfunctions caused by the firing pin retaining pin shearing off in the upper at about 40k rounds. No clue on the lower, it’s been in constant use since 2010- for reference this upper has only been in use since 2019.

View attachment 613444

View attachment 613445

View attachment 613446

View attachment 613447


I can show dozens more. AR’s do not need to be clean- they are filthy little hobbitses and they like it.

My mind is constantly blown by some of these posts. Thanks for the schooling.

 

[PlumberED]

That makes me feel better, I really dislike cleaning my rifles. I have a Surefire SOCOM RC2 on my AR and the rifle is always filthy. I put the rifle together myself and used an H3 buffer, the barrel was made by Ballistic Advantage barrel and has a SA AGB. Without a suppressor the AR was a little under gassed, ejecting the brass at 5 o’clock, with the suppressor installed the brass is ejected at 3 o’clock so I didn’t really need the AGB.

 

[ARK_Ginger]

(I have used olive oil, motor oil, vagisil, brake fluid, etc)

I feel like there's a story behind this.

 

[Formidilosus]

My mind is constantly blown by some of these posts. Thanks for the schooling.

The issue is that what is “known” in the firearms world is almost entirely regurgitated nonsense from incestual inbreeding. Things like “AR’s have to be clean” is repeated ad nauseam without any of the people repeating it ever testing their belief themselves.

 

[Formidilosus]

I feel like there's a story behind this.

Haha. There always is.

“Your rifle malfunctioned again because it’s dry as a bone…? Here, carry this and use it”.

 

[isItFallYet]

My drill instructor says differently! Haha. Mine are filthy, but not that filthy!

 

[Veloci_Wrench]

If you decide to try an adjustable gas block, I recommend getting one that can adjust all the way to the "closed" position, such as the Aero Precision option. Not all adjustable gas blocks are engineered to actually shut the gas completely off.

Then, you can adjust to the minimum amount of gas necessary for reliable function. If one click from "closed" still seems over gassed (which can happen with a given suppressor and/or oversized gas port diameter), throw in an H2 buffer.

 

[DangerRanger]

i don’t know much, but if I could do it over again I would prioritize lower back pressure over most things. My rifle with my turbo k absolutely sucks to shoot unless it’s specifically tuned for the can and now that it is will not function correctly with the can off.

I have never cleaned it but it’s not got form round counts, only like 2-3k idk

 

[SouthPaw]

What is “known” in the firearms world is almost entirely regurgitated nonsense from incestual inbreeding.

@Ryan Avery can we please get a Rokslide t-shirt with this quote on it.

 

[Dobermann]

@Ryan Avery can we please get a Rokslide t-shirt with this quote on it.

Or this:

“Your rifle malfunctioned again because it’s dry as a bone…? Here, carry Vagisil and use it”.