I wanted to do a quick post today with a few of the things I use to simplify suppressors and make them more understandable.
Does a silencer make a gun silent?
Very few guns will be “movie quiet” when shot suppressed. When a gun is fired noise can come from four separate sources:
1) the explosion of the powder
2) cycling of the action
3) bullet breaking the sound barrier
4) bullet striking the target
The silencer muffles the portion of the noise of the powder explosion that would normally emanate from the barrel.
The cycling of the action on a semi automatic or automatic is not muffled by the silencer and is going to be at least as loud as it would be when hand cycled because some of the noise generated by the powder explosion will escape through the action as it opens. This action noise and explosive noise which escapes through the action can be eliminated through the use of firearms with a non-semiautomatic or automatic action.
The bullet breaking the sound barrier is not muffled by the silencer. The speed of sound is roughly stated to be 1,100 feet per second. The exact speed of sound varies and is affected by altitude, temperature, humidity, and barometric pressure. The crack of the bullet braking the sound barrier can be eliminated by the use of subsonic ammunition. Keep in mind that the energy at the target will be reduced significantly by reducing the speed of the projectile, although this may be compensated for by increasing the weight of the projectile.
The noise of the bullet striking the target is not muffled by the silencer and is something we can’t do anything about. It’s kind of the goal.
So, although through proper choice of firearm, ammunition, and silencer you can minimize the noise of a gunshot—sometimes to surprisingly quiet “movie like” levels, this is not the norm. Our normal goal when fitting a can to a firearm is to make that firearm as quiet as possible but at a minimum, we want it to be “hearing safe” which is commonly identified as 140dB.
Three questions that determine if you can use a suppressor on a given gun:
1) Do you have the mechanical means to attach it to the barrel of the firearm? This can be direct thread, quick attach, or some form of adapter.
2) Is the bore of the suppressor sufficient for the projectile to pass through? Obviously a .45 projectile won’t make it through a .30 bore.
3) Is the suppressor built to withstand the muzzle pressures produced by the round? This is crucially important because I can take a lightweight Ti .45 pistol can and thread it to the barrel of a .300 Win Mag with the right adapter (check off question 1). The .30 bullet will easily pass through the .45 bore of the suppressor (check off question 2). However, that suppressor is deigned for a 230 gr. bullet moving at 800-1000 fps generating max CUP of 21,000 PSI , not a 200 gr. bullet moving at 2,800 fps generating max CUP of 54,000 PSI. It could potentially cause the can to explode. If you have any doubts, a phone call to the manufacturer could save your can, your, gun, and your health.