Suppressed SBR owners come in here.

[xxspudxx]

Running a 4.5" barrel though a Spectre II.

Is there a way to keep the gas blowback out of my face?

Ran 500 though it on Monday, was really bad.

 

[beemerphile]

I'd start with a longer barrel. You will also burn your suppressor out pretty fast with that short a barrel. I use a minimum 10.5" barrel on mine and haven't noticed a problem with both a LMT and an LWRC upper.

 

[roadkill45]

the gas is coming out from the charging handle. take some red rtv silicone and run a bead on the top 'U' where your fingers grip. put a releasing agent (a little grease) where the charging handle mates to the receiver and close it up, let dry 24 hrs.
this fills in the gap that lets the gas out. you can also do a basic 'gas buster' type mod flip the CH on it's side and drill a 1/8" hole on the right side and then turn it over and use your drill bit to make an angle hole out of the inner portion of the hole you just made, this will allow gas to escape the hole and go horizontally to your right as it exits the CH. (arf com has an excellent write up with pics of exactly what to do) have done my 15-22's and all my AR's this way and never get 'gas face' anymore.
went and shot 60 rounds with a can yesterday jack rabbit hunting with SS rounds. killed 5, not a good average but i was using an EOtech with 3x magnifier and these jacks were at about 80-100 yards with SS ammo. it does not pack a very good punch at that range, but still, 5 in the freezer for jack tacos is good enough for me.
good luck with the CH mod

 

[strobro32]

I have the same combo and do not get much, if any, gas to the face. I run multiple 200 round drums at a session and have not experienced this effect. My preferred ammo is CCI standard velocity.

What ammo are you using?

 

[xxspudxx]

Beemer: If this was anything other than a .22, I would agree.

roadkill: I will keep this info in mind, thanks for the informative post.

strobro: Mostly CCI SV, had some CCI tactical left over.

Attached is a photo of the upper and lower.

 

[strobro32]

Ok. You gave me a reason to blast through another 200 rd drum w/ CCI SV.

Bear in mind I've done a few modifications to my upper that include yellow springs, bobbed hammer, polished pins and homemade .250" neoprene buffer. And...I always use shooting glasses.

Here's what I noticed. When I pop through the rounds using 4/4 time, I have no problem. When I start rapid firing, I notice the gas. After about 20-30 rounds the gas is bad enough for me to want to present arms for a break.

Funny I've never noticed this before. Thanks a lot. I think another issue that helps the gas issue is shooting on the move. It only when I'm standing in one place without a breeze. Solution, shoot and move.

 

[xxspudxx]

Tell me more about this buffer. Does it help with the action noise?

I seem to notice the gas when standing still, this was the first time I shot it indoors, so moving was not an option. Glasses always, no matter the gun.

 

[strobro32]

The noise reduction with the buffer has yet to be determined. The buffer gives the action noise a different sound. Instead of a clink-clack-clack sound, it goes clink-thud-clack. It would be cool to have similar hosts to run side by side for a comparison.

 

[beemerphile]

Beemer: If this was anything other than a .22, I would agree.

Sorry. My reading comprehension skills took a dump. Never mind!

 

[xxspudxx]

strobro: Im going to play with the buffer idea and see what comes of it. What pins did you polish? Just noticed that.

beemer: Its all good, was still useful info to keep in mind for my next build.

 

[strobro32]

I just got some Flitz polish, rotary tool and cotton polishers. I polished the KNS pins, hammer/ trigger pin holes, hammer face and most surfaces that slide.

Allen_1 talked about it here.
http://smith-wessonforum.com/smith-wesson-m-p-15-22/244556-trigger-job-speed-hammer-pics.html

Most of the noise that comes from suppressed 15-22 comes from bullet impact. The second nosiest part is the bolt hitting the barrel. I had an idea about that one but I'm still working on it. I need a second bolt to play with.

 

[Low_Down]

I never noticed any gas from mine.

 

[xxspudxx]

Ya, its crazy loud when the bolt comes to rest.

 

[Kayback]

Is it only the super short suppressed guns that suffer blow back? I've not noticed it with a 16" and screw on suppressor.

KBK

 

[strobro32]

I think suppressor design has a lot to do with the amount of gas too. My original Spectre and Sparrow II (which is usually installed) creates a lot less gas.

 

[xxspudxx]

Lowdown: Has any damage shown up on the mags or lower yet?

Kayback: It was a non issue at 16"

Strobro: That is a good point. Did they change baffle designs with the Spectre II?

 

[strobro32]

Yes. Both suppressor designs changed last year. SWR went from a thick omega baffle to a thin modified M baffle on the Spectre II. M and K baffles are known for increased blowback. Silencerco did change the design for the Sparrow II. It was a long aluminum monocore to a shorter SS monocore with less baffles. Less baffles create less blowback.

 

[xxspudxx]

Thanks for the info.

 

[roadkill45]

just to throw in with the mod on the CH, i'm running an AAC Pilot, AAC Pilot II, Gemtech Sandstorm (7.62) Gemtech Trek (5.56) and a Gemtech Trek Ti is in the waiting line for this month. they all run on 16" guns. I was only getting a little bit of gas face, but i wear glasses so it was not too much notice, plus i don't shoot at an inside range..just go out to the desert, so the gas may be there, but is blowing to to the side and away.
Here is a link to the red RTV fix, works great::
Do It Yourself Gas Busting Charging Handle [2009-09-29] - 03DESIGNGROUP

and one for the DIY gas vent:
Gasbuster charging handle?? - Sniper's Hide Forums

 

[xxspudxx]

Thanks for the info! I think I will be doing this when I get a new charging handle.