Is this much blow by normal for suppressed AR?

smith1559

smith1559

New member
I have been shooting suppressed ARs now and I can't believe how much blow by there is. I did get the PRI gas buster charging handle but it is still pretty bad. I am using H322 powder in this picture. On the right is new rounds not fired. (For comparison)On the left was new rounds and I fired 3 rounds out of the magazine and this is what the rest of the rounds look like. Is this just the norm or does it seem execesive...Jason

CA6944E0-E045-467C-9FD8-2D40BF3D450F-19102-00001E12763A5E20_zps0f6725ef.jpg
 
Originally Posted By: ksduckhntrIf a piston system was used to it reduce the amount of blowback when suppressed?

Or an adjustable gas block???

I'm no AR expert and know even less about suppressors but would suspect that adding a suppressor (= longer "barrel") would increase the time gas pressure is up after bolt unlocks, thus allows more blowback??????????

Someone more knowledgeable on the subject please enlighten me.

Regards,
hm
 
The Gas Buster CH is to divert the excess gas caused from using a can away from your face. It does nothing to reduce the amount of gas forced back into the chamber from the can. A Noveske switchblock or other adjustable block will eliminate a good portion of the excess gas, but will not keep your brass bright and shiny like on a bolt gun. I had a 18" midlength Switchblocked barrel before I went SBR, the brass was just as dirty as my SBR barrel is without an adjustable block. I just didn't get a bunch of gas in the face every time I pulled the trigger. I get a little gas blowback now, but for some reason it doesn't seem as bad as that 18" barrel was. Suppressed gas guns are dirty and there's no getting around it. Yours aren't don't look as bad as mine, it's just an extra benefit you get when using a can.
 
Originally Posted By: hm1996Originally Posted By: ksduckhntrIf a piston system was used to it reduce the amount of blowback when suppressed?

Or an adjustable gas block???


hm
This is a round out of the chamber of my 6.8 SPC after multiple shots at a sounder of hogs.

2zix7yF.jpg


I installed an adjustable gas block which made the blowback problem a lot better.

http://www.jprifles.com/1.4.6_gs.php

I also just bought a new RRA LAR8 and installed an adjustable gas block before putting a round through it.

LCpvQbA.jpg
 
Last edited:
Originally Posted By: hm1996Originally Posted By: ksduckhntrIf a piston system was used to it reduce the amount of blowback when suppressed?

Or an adjustable gas block???

I'm no AR expert and know even less about suppressors but would suspect that adding a suppressor (= longer "barrel") would increase the time gas pressure is up after bolt unlocks, thus allows more blowback??????????

Someone more knowledgeable on the subject please enlighten me.

Regards,
hm

Adding a suppressor creates more back pressure so your rounds and weapon will dirty faster. The way I solved the problem is once you start shooting you don't stop till you run out of ammo.
smile.gif


Seriously though its never been a problem. A couple of dirty rounds that can be wiped off is a small price to pay for having silent death at your disposal.
smile.gif


Everything I shoot is suppressed... anything less is uncivilized..
smile.gif
 
Looks normal to me. Just the way it is. 3DHuskers post above is spot on. Honestly I can't remember the last time I shot unsuppressed. Anyway yea they get dirty but the benefits far outweigh the other things. Good shooting!
 
I had a feeling this was pretty normal, But I love the suppressor. I will try an adjustable gas block on one AR and see if its worth putting it on them all...

Thanks...Jason
 
Just an FYI.....I modified a couple of my Charging handles based on a UTube video showing how instead of buying the Gas buster. After looking at the Gas Buster I was not sure it would help a Left-handed shooter. The modification is simple and inexpensive just buy a tube of High Temp gasket sealer about 7.00 easy fix.
To be honest I never really got any gas blowback in my face to speak of anyway not sure if it is because I was shooting left-handed or not. Friends that shot my guns Suppressed noticed it so I modified a couple of the CH's just to see and they have held up fine but I cannot really say how well they perform to eliminate the problem.

Oh my brass looks really dirty too.
 
Last edited:
Yours is normal and due to back pressure caused by the slowing of gasses in the silencer. Pressures vary by make/model of suppressor among other things.

The YouTube silicone sealant CH fix helps as does an adjustable gas block. I have Noveske SwitchBlocks and others. Noveske is well built, simple, and effective. But they lack the number of positions other adjustables have. Many use set screws which offer infinite settings but are tough to change once fired many times.

Look hard at a Syrac Ordnance adjustable gas block. They adjust with a detent and Allen key rather than a set screw design. Syrac has a better mouse trap.

Sendit
 
I own a syrac on my 16" mid length. It works as described. You can completely turn off the gas or give it as much as you want. I think the thing I like the most about the adjustable gas block is that I no longer have to go looking for brass 15 feet away.
 


Write your reply...
Back
Top