Suppressor 1st shot?

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Magnuumpwr

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Has anyone played around with a 308 suppressor to get the oxygen out for first shot suppression? I ask because my paperwork is due to come back for my suppressor and I want to take it out hog hunting. Problem is when the test model was fired, the first round was very noticable. The dealer told me that it was loud because it burnt the oxygen to cause the sound. I have been toying with the idea of using a spray can of keyboard duster to inert my suppressor to attempt 1st shot suppression.
 
From talking to guys who shoot hogs with suppressors ALL THE TIME (4-5 nights/week), the suppressor noise isn't what spooks them - it's that unmistakeable sound of lead hitting pork. When they hear that and the first little piggie next to them goes down, they're outta there - muzzle noise or not.

That said, I'd love to hear from others here with more suppressor experience as to what causes the first round "pop" and how it could be mitigated.

Check out tacticalhogcontrol.com for some cool videos from the guys I'm talking about...
 
From what I understand, first round pop is caused by the oxygen that is in the can before it is fired. I don't have much knowledge about rifle suppressors, but I know that pistol suppressors can definitely be shot wet to help alleviate the FRP. For example, some of the small pistol suppressors that are designed to be shot wet and wiped have very little, if any, first round pop.

The only reason I might be hesitant to shoot a rifle can wet is the large increase in pressure over that of a pistol can, but I don't believe it would be a problem if you started with just a little bit of water/ablative and worked up. In theory though, all you have to do is displace the oxygen before firing, so that keyboard duster spray might work.
 
On another forum, I was told that spraying it out with canned air (keyboard cleaner) then putting stickers over the holes (til used) would get and keep the oxygen that causes FRP out just fine :)
 
Essentially, no small arms propellent has enough oxidizers in it for a full burn. In addition, the combustion products are themselves flammable. The gasses aren't actually all that hot, until they start to hit the baffles, at which point all the kinetic energy in the barrel gasses gets converted to heat.

The result is that when the high temperature flammable gasses from the barrel are mixed in with the oxygen in the suppressor, the propellent gasses burn brightly. (Oxygen doesn't burn, it enables burning) The bigger the internal volume of the can, the bigger the pop, at least in my experience.

The prong type flash hiders work by cooling down the gasses below the ignition temperature before they get a chance to mix with air (or that's the theory at least).

OP, a few drops of water works wonders for the first round pop also...
 
Thanks for all the replies. Wasn't sure if inerting the suppressor would cause any odd problems. I know weird stuff has happened doing less.
 
Keep firing the can until broken in. It's just like seasoning a barrel. All of mine slowly but surely keep dropping the decibles until the brake in period. Use subsonic ammo,do your homework to achieve optimum results. Let me see if I can post pics.
 
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First round pop is only a consideration when using a suppressor with subsonic ammo. If using supersonic ammo, the FRP is drowned out by the supersonic crack of the bullet and won't be noticed.

As such, FRP is most noticeable in subsonic cartridges such as 22lr, 45, and heavy 9mm. That being said, the design of the suppressor is what determines whether you have FRP at all. My gemtech alpine has absolutely zero perceivable FRP. Nor does my integrally suppressed 77/22. My YHM mite on the other hand has a very audible FRP and is a loud can even after that. Efficient K-baffle designs with very sharp edges reduce FRP if not completely eliminate it. Monolithic cores with plain "washer" style baffles have a lot of FRP.
 
Orkan, that's not true in my experience. The first round pop is quite noticeable on every centerfire can I've fired, including Gemtech, KAC, AAC
 
Orkan, that's not true in my experience. The first round pop is quite noticeable on every centerfire can I've fired, including Gemtech, KAC, AAC
I spend the bulk of my time with 308 and 338 out of bolt rifles using YHM 30cal and 338cal suppressors, and I've simply not noticed it. My experience with other suppressors on rifles has been pretty limited. Maybe the YHM's just don't have much FRP?

I'm not discounting what you are saying, but there must be some reason for our vastly different experiences.
 
I'm sure you can pick up FRP if using a dbmeter. Maybe its just my bad ears. No one I shoot with has ever really noticed or complained of FRP unless shooting subsonic.
 
Orkan - that is consistant with what i've read, mono core suppressors have more FRP that a stack of K baffles. i've actually heard it enough times that it played a part in my silencer selection. i ruled out some cans that had mono cores, not solely because of that but it did play a part.
 
Orkan - that is consistant with what i've read, mono core suppressors have more FRP that a stack of K baffles. i've actually heard it enough times that it played a part in my silencer selection. i ruled out some cans that had mono cores, not solely because of that but it did play a part.
Yup. Case in point would be the AAC TiRant 45 vs the Silencerco Osprey. Osprey has FRP, while the TiRant does not. The osprey is not hearing safe on its first shot, while the TiRant is.

If you compare the baffle stacks... you'll clearly see why.
 
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