Suppressed, SBRed AR-15?

[Chris Rhines]

I feel like building up a lightweight AR with a 10.3" barrel. I would like to be able to run it both suppressed and un-suppressed without changing the setup.

Should I use an adjustable gas block? Will I need to adjust the gas system when mounting or removing the suppressor (this would be less than ideal)?

Any insight into buffer, gas port diameter, gas system length, etc.?

Thanks all,
Chris

 

[ronin111]

You should always loctite an adjustable gas block after you've found your sweet spot. They usually aren't designed to be adjusted on the fly and repeatability would be difficult. You could use one to find a setting that works both unsuppressed and suppressed.

Check out the Noveske Switchblock. It has three settings; on, suppressed and off. It helps with the gas in the face too.

I use a H2 buffer and standard spring on a Noveske 10.5 with a Switchblock. It works like a champ.

 

[ronin111]

What suppressor are you planning on using? A short barrel will cause more erosion to the baffles than a longer barrel. Some guys use a muzzle brake mount for quick attach suppressors to take the brunt of the erosion, it acts as a sacrificial baffle.


These aren't my pictures but I believe this was about 2k rounds through a 12inch.

The blast baffle has minor erosion.


The muzzle brake took the brunt.

 

[UnknownGunMan]

Looks like you mighta been shooting corrosive surplus ammo...

 

[ronin111]

Not mine but I believe it was standard 5.56, probably XM193. It's the unburnt powder and hot gasses causing the erosion.

I don't think anyone would shoot corrosive ammo through a can. I doubt it would cause any difference in erosion but would most likely corrode the internals.

 

[PTK]

Silencers are generally not worried about corrosive salts. My M4-1k from AAC saw plenty of 5.45x39 corrosive.

Also, I suggest a 11.5 or 12" barrel for SBR and silencer use - good blend of velocity, length and reliability.

 

[Chris Rhines]

The can will be (is) an AAC M4-2000 with a Brakeout mount. I'm very much down with using the $80 brake as the first baffle.

I'd prefer to avoid the Switchblock if possible, because it won't fit under a float tube.

-C

 

[rjrivero]

I have an Ops Inc 16th. I run it on my 7.5" upper, my 11.5" upper and my 16" upper rifles. The 7.5" is obviously a pistol length gas tube, and the others are carbine length.

Never really worried about the guns being over-gassed with a can. No one that I shoot with worries about over gassing their guns with their cans either. None of us has an adjustable gas block.

One guy runs a Halo, one runs an Ops Inc 12th and one runs an Ops Inc 14th.

 

[PTK]

The can will be (is) an AAC M4-2000 with a Brakeout mount. I'm very much down with using the $80 brake as the first baffle.

I'd prefer to avoid the Switchblock if possible, because it won't fit under a float tube.

-C

With that setup, grab a nice chrome-lined 1-in-7" twist 12" barreled upper - you'll LOVE IT. No need for a switchblock, good velocity, fantastic reliability, and very little over-gassing (still, it's an AR-15, so... )

I've used that setup, but with a M4-1k, and I loved it.

 

[V.Oller]

Here is a pic of my canned SBR.

Spec: Noveske lower with RRA 2-stage trigger. Upper is DPMS with Stag BCG and 11.5 inch barrel. AAC Blackout flash suppressor.

Suppressor is a AAC M4-2000.

So far, no erosion marks...

 

[ronin111]

Silencers are generally not worried about corrosive salts. My M4-1k from AAC saw plenty of 5.45x39 corrosive

I stand corrected. AAC says there good to go. I had always been under the impression that it would still cause corrosion after a while even with stainless.

 

[Ironman]

My noveske 10.5 is standard w/o the switchblock and it runs fine suppressed and unsuppressed with a 51tbrake/m42000.

Link with info and video...

http://www.silencertalk.com/forum/viewtopic.php?f=13&t=66880

Video
http://www.youtube.com/watch?v=6R7Oh7rQJBQ

 

[bkjeffrey]

My 7" 1-7 ASA barreled sbr. Uses a standard low profile gas block and typical pistol length gas tube and a standard H2 buffer. It runs just fine. Im not sure about gas port size, whatever is came with from ASA is what it is.

 

[mrnkc130]

My 10.5 SBR runs fine with our without the can - YHM stainless phantom

Probably have about 1k rounds through this can on the 10.5 and havent seeen any signs of erosion yet...

 

[Zak Smith]

I have a 12" Noveske upper that runs fine suppressed or normal. Here's a 7" that prefers to have the can on

 

[tarosean]

Stupid question...

Do SBR's w/ suppressor's have to have 2 tax stamps or does 1 cover it?

 

[W.E.G.]

2 stamps

one for the receiver, and one for the can

$400

 

[jmorris]

You have to have two stamps unless the suppressor is made into the barrel and oal is 16+.

I did just that on this 9mm AR





For 223 and a 10.5" bone stock works just fine and makes a dandy truck gun.

 

[tarosean]

You have to have two stamps unless the suppressor is made into the barrel and oal is 16+

Does that basically mean it cannot detach?


Sorry for the ignorant questions.

I am wanting to get into the SBR game with a HK USC w/ a shorter barrel. Dont want the entire UMP conversion just a shorter barrel w/ a real suppressor not the fake ones they sell for it...

Clean record and live in TX so its really just a matter of time and knowledge.

 

[TXSurf]

Tarosean,

That is correct, to just be a one stamp gun, the suppressor would need to permanently attached and give an oal of 16" or greater.

Best bet for the HK you're wanting to do would be to register the receiver as an sbr and register the suppressor on its own, which means you're paying two tax stamps, which would allow you to shoot the gun in both suppressed and un-suppressed setups. And it also gives you a suppressor to use on any other host in that caliber, instead of having it stuck to the rifle

 

[TexasRifleman]

And it also gives you a suppressor to use on any other host in that caliber, instead of having it stuck to the rifle

Yeah unless it's some highly unusual gun you don't want an integral suppressor. For AR type rifles you want to be able to remove the suppressor to either use on another firearm or send in for overhaul/maintenance if needed.