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tpelle
26 February 2012, 15:07
I 'm confused about why anyone would want a suppressed Ar15, and am hoping someone can set me straight. Honesty. I'm not trying to be a troll here, but wish to be educated.

Here's why I'm confused :

You see, I shoot Highpower Rifle. As part of an across-the-course match each competitor pulls pit duty, where you are downrange behind a berm, and are pulling and scoring targets. The targets are mounted on a frame which can be pulled down behind the berm for scoring, pasting, and marking.

During the slowfire stages, for instance, each shot is marked individually, and you know a shot has been made on the target you are scoring by two ways - you see a bullet strike in the backstop behind your target, plus you hear the sonic boom of the bullet passing overhead.

The sonic boom is what puzzles me.

When a bullet leaves the barrel of a rifle at supersonic speeds (and a 5.56/. 223 bullet is definitely travelling in excess of supersonic) it forms a standing shock wave that it sort of pulls behind it, similar to the bow wave of a boat. As thar shock wave passes your ears, you hear it as a sharp crack! You don't even hear the report of the cartridge going off.

The phenomenon of that standing shock wave - the sonic boom - is produced by the bullet passage through the air at the speed that it is traveling. I don't understand how any device affixed to the barrel of the rifle can change that!

I could see how, if you were to fire special subsonic ammo, and had a device that absorbed the gas pressure from the firing of the cartridge as it left the muzzle, then you would have a truly sound suppressed firearm. But how does this work for an AR15?

TangoSauce
26 February 2012, 16:40
I think most run a suppressor to remove muzzle flash while running a compensator. However, I believe to which you are referring is that the sound of the bullet going super sonic can not be easily identified from a specific direction when shot suppressed.

Eric
26 February 2012, 16:49
Running a suppressor isn't about noise elimination. That's obviously impossible, especially with a round traveling at supersonic speeds. However, a good suppressor will greatly reduce the loud blast emitted from the muzzle, which is especially helpful in indoor/CQB applications.

csmith
26 February 2012, 17:35
tpelle,

I asked the same question a while back. Eric gave you the same basic answer, but this may help.

http://www.weaponevolution.com/forum/showthread.php?3623-General-NFA-Questions

markm
1 March 2012, 09:12
I 'm confused about why anyone would want a suppressed Ar15, and am hoping someone can set me straight.

Suppressed shooting helps us be able to hear gong hits at distance. The supersonic crack isn't the issue with a suppressed AR... it's the ejection port noise. Run the same can on a Bolt gun and the sound from the shooter's position is AMAZINGLY different... much quieter than a gas gun.

From the shooter's position, the supersonic crack isn't bothersome at all. But if you step forward of the muzzle10 yards... the report from a suppressed AR hurts your ears. It's amazing how loud it is in front of the silencer.

Koshinn
4 March 2012, 16:08
I 'm confused about why anyone would want a suppressed Ar15, and am hoping someone can set me straight. Honesty. I'm not trying to be a troll here, but wish to be educated.

Here's why I'm confused :

You see, I shoot Highpower Rifle. As part of an across-the-course match each competitor pulls pit duty, where you are downrange behind a berm, and are pulling and scoring targets. The targets are mounted on a frame which can be pulled down behind the berm for scoring, pasting, and marking.

During the slowfire stages, for instance, each shot is marked individually, and you know a shot has been made on the target you are scoring by two ways - you see a bullet strike in the backstop behind your target, plus you hear the sonic boom of the bullet passing overhead.

The sonic boom is what puzzles me.

When a bullet leaves the barrel of a rifle at supersonic speeds (and a 5.56/. 223 bullet is definitely travelling in excess of supersonic) it forms a standing shock wave that it sort of pulls behind it, similar to the bow wave of a boat. As thar shock wave passes your ears, you hear it as a sharp crack! You don't even hear the report of the cartridge going off.

The phenomenon of that standing shock wave - the sonic boom - is produced by the bullet passage through the air at the speed that it is traveling. I don't understand how any device affixed to the barrel of the rifle can change that!

I could see how, if you were to fire special subsonic ammo, and had a device that absorbed the gas pressure from the firing of the cartridge as it left the muzzle, then you would have a truly sound suppressed firearm. But how does this work for an AR15?

To the shooter, a suppressor helps a lot with noise and it definitely helps with concussion and blast kicking up dirt and other crap on the group.

Suppressors also almost completely eliminate flash (depending on barrel length, suppressor length, etc).

chase45
8 March 2012, 15:18
They are about as loud as a .22

The tone is way different than a unsuppressed gun shot. Sounds like a paintball gun on steroids.

Really the suppressor eliminates the sound of the gunshot, for the most part. The only thing you are really hearing is the crack of the bullet breaking the sound barrier. I had my friend shoot mine 100 yards away from me in the woods. You couldnt really tell where the shooter was, only could hear the round zipping through the air. Its hard to describe unless youve heard it before

Suppressors are badass

http://i301.photobucket.com/albums/nn63/cclement45/IMG_5855.jpg

markm
12 March 2012, 07:04
You hear occasionally that the suppressor masks the shooter's position at distance. But that's not how it really works.

We fired past some some buddies who were 200 yards in front of us. The target was 235 yards beyond their location. They could not hear the difference between supressed and unsuppressed because the super sonic crack of the bullet passing masked any muzzle report.

I laugh when these "experts" on the mil channel tell you... "they'll never know where it's coming from". Well... true... but not because of the silencer. It's where you first hear the crack that creates the perception of the shooter's location.

uspopo
12 March 2012, 14:26
Not mention that it is fun as hell to shoot!!

Stan