PDA

View Full Version : Using an Expansion Chamber instead of a Suppressor?


ultraman20000
February 13, 2008, 06:34 AM
Hi this is my first post. Mostly I have browsed around on here and have been able to find answers to my questions through search.

Anyway, I'd like to have a suppressor in order to help save my hearing, but I don't want to have to pay the ridiculous tax to get one.

I thought about making my own, but through browsing on here, I've learned that it's illegal. I've also learned that when people talk about doing illegal things like that on here, their threats get locked. I'm not talking about making suppressors - this post is not about doing anything illegal or about talking about doing anything illegal. I'm asking this post to find out about a possible legal alternative.

So I was searching on the internet and found this page (http://anarchangel.blogspot.com/2007/06/this-is-not-suppressor.html) where they were talking about putting a tube in front of the muzzle for the gas to expand and to direct the sound/flash forward, and how this would help decrease the sound from behind the gun.

They say that this will work and that because you wouldnt have baffles, it's not a suppressor:
From a technical standpoint; if a muzzle device has baffles or any other sealed chambers or constrictions in front of the muzzle, it's a suppressor; if it has no sealed constriction in front of the muzzle, it’s an expansion chamber.

Has anybody tried to make something like this or use something like this? If so, how did it work? If you no longer do this, why not? Also, if anybody is aware of the legal definitions of what is a suppressor and what isn't, please share. I imagine that this might not be seen as a suppressor, but more like a sound director.

Also, I was looking online and saw that one company that manufactures suppressors also sells "fake suppressors" (http://www.tacticalinc.com/fake-suppressors-c-126.html). It looks to me like they are selling the suppressor casing without the internal baffles. Perhaps this might kind of work like an expansion chamber and lessen the sound, or at least direct it away from me? Surely if these people can sell something like this, it must be legal. Has anybody tried one of these out.

Thanks

oldbillthundercheif
February 13, 2008, 07:02 AM
This is the only thing I can think of that works (supposedly, anyway) and is legal:
http://i89.photobucket.com/albums/k223/zarganuts/MetroBarrel.gif

Do an internet search for "Metro Shotgun Barrel" and you will be knee-deep in info.

The fake supressors don't do ANYTHING. If they did, there would be a legal problem.

wjkuleck
February 13, 2008, 09:18 AM
The ATF has declared that any sound reduction constitutes a suppressor, and is subject to tax & registration. Now, how do they make that determination? Is it sound at the shooter, at 90 degrees to the firearm, in front?

AFAIK, they won't say.

Get a pair of Leightning muffs (NRR 31 db) and a set of fitted occluding ear plugs, and learn ASL.

Regards,

Walt
PS I'm not sure how EAB gets away with that barrel; I must ask sometime.

Slopemeno
February 13, 2008, 10:20 AM
Buy a decent air pistol and substitute it for practice sesions. A Daisy 717 is a bargain, and you can shoot in your garage.

wjkuleck
February 13, 2008, 01:07 PM
Buy a decent air pistol and substitute it for practice sesions. A Daisy 717 is a bargain, and you can shoot in your garage.

Great idea!

Regards,

Walt

ultraman20000
February 13, 2008, 10:18 PM
Buy a decent air pistol and substitute it for practice sesions. A Daisy 717 is a bargain, and you can shoot in your garage.I don't really like airguns. I want to have fun shooting lots of 22lr

oldbillthundercheif
February 13, 2008, 11:03 PM
You may just want to eat the $200 fun-tax and get something that you know is legal and functional. It's a pain in the hindquarters, but the safest option by far.

44 AMP
February 14, 2008, 12:45 AM
But in the past, the ATF has considered it a crime to attempt to silence a firearm. In other words, even if your homemade silencer didn't work, you would still be tried, and likely convicted, because it was your intent to break the law.

Shooter urban legend (may be true, but I can't give references) told of one guy who was convicted of attempting to silence a firearm, and went to jail over it, when his homemade silencer actually increased the noise of firing by 1db! Don't know heo they look at it today, but if it is the same as in the past, anything you attach to the barrel with the intent of reducing the noise would be considered a crime, whether it worked or not.

The extra long barrel shown would not be considered a silencer, just a long barrel, which would reduce the sound of the discharge measured at your ear(because the muzzle is further away), but would not change the sound measured at the muzzle.

JohnKSa
February 14, 2008, 12:59 AM
...but would not change the sound measured at the muzzle.In general, the longer the barrel, the lower the gas pressure when the bullet exits. The lower the gas pressure when the bullet exits, the quieter the sound. A long barrel will definitely make a gun quieter at the muzzle, all else being equal.

oldbillthundercheif
February 14, 2008, 01:02 AM
The extra long barrel shown would not be considered a silencer, just a long barrel, which would reduce the sound of the discharge measured at your ear(because the muzzle is further away), but would not change the sound measured at the muzzle.

That's not how those barrels work. As I recall the bore size increases gently over the last several feet to allow the gasses to pass the wad and shot and disperse in a less violent fashion. The extra volume of the huge tube also decreases pressure by allowing the gas to expand into a much bigger area before it is completely released.

I think they are also used with extra-light loads to make the system work better.

That's what I remember, anyway. I'm sure there is a website out there with a more precise explanation.

rkba_net
February 14, 2008, 05:56 AM
The ATF has declared that any sound reduction constitutes a suppressor, and is subject to tax & registration. Now, how do they make that determination? Is it sound at the shooter, at 90 degrees to the firearm, in front?

AFAIK, they won't say.


They measure it like everyone else in the industry... according to MIL-STD-1474D.

Double Naught Spy
February 14, 2008, 07:16 AM
I don't know that I would want to have to argue a case in court that my redirected sound expansion chamber that I attached to my gun isn't actually a suppressor.

saspic
February 14, 2008, 08:15 PM
Anything not attached to the firearm wouldn't be considered a supressor, right? I've seen pics of people shooting through large tubes lined with foam, but that's probably of more help to people outside the immediate vicinity, not the shooter.