When I shoot my SBR (LWRC M6A1 upper/RRA lower) with my YHM SS Phantom that I actually end up inhaling a lot of gas. I love shooting with the suppressor because it does not traumatize my ears as much as normal, but that gas blow back really sucks. Yesterday a friend of mine commented that I had smoke coming out of my mouth and nose after shooting a string.
I have a PRI Gas Buster CH on it and even tried the hi-temperature Silicone seal to no avail. So my questions is, outside of not using the suppressor or wearing a gas mask, what other options I have to minimize my inhaling this stuff?
That’s what worries me. I just got my lead levels back down to normal. I used to teach a lot of basic Pistol classes in an Indoor Range and the .22 ammo we were using were all non-jacketed. It took a good 6-years for my body to dispose of the extra lead.
I guess it’s a good sign that I actually breathe when I shoot. But it can’t be very healthy for me.
I’m not certain that there’s lead in that gas, but logically… there could be.
I mean… a certain amount of lead off of the base of the bullet will surely vaporize behind 1200 degrees of propellant burning. And the can is trapping those gases and pushing some of them back in our faces.
I don’t know if it will help you or not, but I run H3 buffers in my 11.5/12.5" guns and I can tell a noticable difference when firing suppressed between the H3 and H buffers. I emailed Ken Elmore at S.A.W. about this once and his recommendation was basically this: if running a AR15/M16 suppressed, especially short barreled one’s; they should be on the verge of not functioning without the can on. He told me that on an 11.5" gun, the best buffer choice would be the special purpose “X” buffer for 9mm carbines. When the can comes off, the buffer gets replaced with the H3. He said the gun would probably not run well with the X buffer alone, but would run the best suppressed with the least amount of stress on internal parts with the X buffer. I should have saved that email, hope this helps.
Yeah, but I’m not about to give up shooting. I managed to minimize my exposure to lead by giving up reloading and reducing my indoor range sessions (and it worked).
I do wonder about the ammonia content. But I don’t notice it all that much though.
I’ve seen people shooting with these things at the indoor range. I believe the activated charcoal filters capture airborne lead and other contaminants. Obviously you can’t really shoot a rifle with the model pictured, but you should be able to find smaller profiled ones if you look around. You can also check out your paint stores for these.
How do the piston uppers affect the amount of smoke and ammonia smell? I know some gas is coming via the chamber after looking at my brass after shooting suppressed. Its just a matter of how much compared to the gas tube. Guess it still vents though just further up with a piston upper.
If you want to try buffers you may could try a David Tubb carrier weight in combination with a heavy buffer. That way you could tweak the weight a little easier. I bought a H3 buffer from “Heavy Buffers” and he will sell the individual weights as well. He had steel, tungston and lead last time i checked and if yuou knew the weight you wanted he can custom make it as well. The e-mail is heavybuffers(at)gmail(dot)com. My 16inch midlength upper functions fine suppressed and non suppressed with the heaviest tubb carrier weight the h3 buffer and a tubb flatwire spring. That may or may not work for you as we all kniow all rifles dont act the same. Also remember if your using a carbine stock and have a fixed stock buffer you can cannabalize the weights to make a different weight buffer.
Im glad i found your topic as i was really considering SBRing my lower and building a 10.5 upper to shoot primarily suppressed.
The piston upper actually reduced the amount of blow back. I don’t worry about gases hitting me in the face as it did when I was using a DI system on this.
What really affects the gas blow back is the suppressor. If you look at the video, you’re see that the gases are coming out of the ejection port.
I have been shooting the SBR without the suppressor lately and I prefer it that way. theonly issue is that it does require some good hearing protection (IE: Surefire EarPro Defender Plus).
There IS ammonia in the spent gases. This is what causes the ammonia smell and this is what causes the ammo to be non-corrosive.
Corrosive ammo does not have the ammonia smell and many people use windex containing ammonia to neutralize the salts that are corrosive.
I guess if you make the powder with chemicals that will produce ammonia when burned, that will neutralize any problems…
Piston uppers keep the higher pressures out of the bolt and carrier and it is those which force those gasses out of the cracks around the charging handle.
Also, gas from the gas tube travels down the key and pushes the bolt forward and carrier rearward. Excess gas vents through the holes in the side of your carrier and you usually get some of that back in your face too.
I’m finding that I get more gas out of the upper and ejection port with my 16" Colt 6920 upper with the PWS piston kit on it with my M4-2000 Mod 1 mounted and it on the suppressor setting. More gas than if the can wasn’t mounted and it’s on the regular setting. I’m finding that the suppressor setting really only makes the rifle operate close to the same bolt velocity as it normally does unsuppressed and makes recoil stay the same.
With my direct inpingment 10" SBR unsuppressed vs. suppressed, the felt recoil to the shoulder increases as does the amount of gas coming out of the upper/ejection port while running the suppressor. The muzzles lifts less with the cam mounted (acts as a comp, I think mostly because of it’s weight for muzzle lift and it makes the recoil more linear).
Well darn. The reason I was looking to get the PWS piston was to help control some extra gases and fouling. I guess I can save the $400 and just invest in a gas buster?
That makes two of us. Even with my heavy weights i still get a decent amount of blowback so i dont think timing the bolt is possable either.
My current setup though i havent had a high round count with it between cleanings is:
H3 buffer: 5.4 oz
Tubb carrier weight with carbide insert: 4.05 oz.
Tubb flatwire spring: Says 22% extra power vs standard spring and 10% vs their round CS spring.
With that said my shooting buddy feels my rifle actually has more recoil with the weights. Since i havent had that high of a round count between cleanings i wouldnt call it reliable yet. I have also tried the high temp silicon on the charging handle with no real big change. Then again it could have been this ejection port issue we are discussing causing the sensation it wasnt working.
Other than careful handloading and testing powders and primers i cant think of a good way to reduce the smoke.
A friend of mie has the Phantom and it gasses him quite a bit as well.
My 10.5 LMT and M4-2K combo gassed me a fair amount even with the gas buster c/h, but then I did the silicone RTV mod to it and that made it alot more pleasant when shooting from my right shoulder; when shooting around barricades from my left shoulder, I got all the gas from the ejection port in my face.
