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The tax stamp is a one time tax PER class 3 item. So, for the suppressor for my .308 its $200, I'm also plan to have a suppressed .22 built at some point, and it'll be another $200 for that suppressor. The forms require a serial number for the item being registered, and you have to get finger printed etc. The item in question is actually registered or licensed to you, and kept on record. Its a hassle, but doable. The same applies for other class weapons like Automatic rifles.

MEL
 

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The tax stamp is a one time tax PER class 3 item. So, for the suppressor for my .308 its $200, I'm also plan to have a suppressed .22 built at some point, and it'll be another $200 for that suppressor. The forms require a serial number for the item being registered, and you have to get finger printed etc. The item in question is actually registered or licensed to you, and kept on record. Its a hassle, but doable. The same applies for other class weapons like Automatic rifles.

MEL
 
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Well from my understanding you have to pay that $200 transfer tax for each suppressor or full-auto you buy. But that still isn't horrible for the fun you will derive from owning one of these. I have also scene plenty of good-quality suppressors for around $500, bringing the total price to only about $700. Not too bad!

Now for MY question concerning muzzle velocity from a suppressor: what exactly is this purported "freebore boost" that i have heard about? It seems that that would mean an INCREASE in velocity from the suppressed vs. unsuppressed...
 

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Jake:

The claim is that, since the bullet is no longer touching the barrel walls, friction should be reduced... However, that fails to take into account two things: Since the suppressor lets the gas expand prior to leaving the barrel, there is a drop in pressure behind the bullet, so acceleration drops, and, since you know get free space around the bullet and all gas didn't expand to the sides, and gas follows the path of least resistance, it can now leak past the bullet in larger quantities, increasing the density in front of the bullet.

Yep, brought out some of my physics notes....
 

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I should have gotten into this battle of wits earlier, but I just love watching you guys duke it out! A suppressor works by slowing down the release of gasses. It is basically the same difference between popping a baloon and just opening the neck and letting the air out. One goes BANG, the other goes pfft! Regardless of the technology employed, slowing the gasses is the object.

A muzzlebrake works by redirecting the gasses to offset recoil. This utilizes exhaust gasses to create a rear-facing jet effect to slow recoil (and/or upward to reduce muzzle rise), kind of like thrust reversers on a jet are used on landings to slow the aircraft. Exact same principal.

A suppressor WILL have an effect on recoil because of two factors. First, you are adding weight to the weapon (assuming that the suppressor is an add on accessory), so that will dampen recoil in and of itself. Secondly, you are slowing the exhaust gasses so you are reducing the jet effect leaving primarily momentum to produce recoil. A PROPERLY FITTED suppressor should not effect accuracy or velocity. The bullet should not make contact at all with the inside (or outside for that matter) of the suppressor, so the only effect on accuracy will be that resulting from the changes in barrel harmonics induced by the suppressor's presence. Since the bullet is essentially in free-flight once it enters the suppressor, there should also be no change in velocity from that of the same barrel sans suppressor. There are a FEW exceptions to the free-flight statement, but these will be limited primarily to small-caliber (rimfire) designs with INTEGRATED suppressors. Thus ends the SIMPLIFIED physics lesson for the day.

K2
 

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Archangel:

That's just one design. There are countless others.

K2:

You forgot that the gases expands quicker than the bullet moves. Some of it _will_ leak in front of the bullet, increasing air density and pressure in front of it.
 

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Nek:

Yes, gases will leak by and increase air density in front of the bullet, but as you said, the gases are moving faster than the bullet. This means that the resistance of the denser gas in front is offset by the higher pressure of the still expanding gases to the rear.

K2
 

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K2:

Except that, as you yourself noted, the purpose of the suppressor is to let those gases expand prematurely, so the pressure behind the bullet will have decreased enormously.
 

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Nek:

Same rule applies in front of the bullet. The pressure will still be higher behind the bullet than in front. The velocity of the bullet, even at subsonic speeds, will always outpace pressure equalization unless you have a VERY long barrel and a VERY long supressor. In that case it is technically possible to achieve equal pressure front and rear, but then increased density is no longer an issue because :D pressure is equalized.

K2
 

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K2:

That would be true if the barrel was perfectly sealed until the bullet arrived at the suppressor. In reality, a lot of gases leak even before that, and as the bullet reaches the suppressor, it suddenly, explosively, expands to the sides as well as around the bullet instead of forward directly against the base of the bullet, effectively removing that push, and at the same time increasing density in front of the bullet. A similar problem was encountered by the germans when they built Grösse Berta during WW1. Building the barrel was a complex project not only because of the forces involved, but also because when the barrel became too long, the shell suddenly started losing velocity, because too much gas leaked in front of the bullet. And they had no expansion chambers such as a suppressor to contend with.
 

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Nek:

You're going to force me to dust off my chronograph and run tests aren't you. I have access to a suppressed 700P in .308. If it ever stops raining here long enough, I'll test both match and subsonic ammunition with and without suppressor to see what happens. You've got me curious now since I remember reading about some of the problems encountered by the Germans in WW1. I'll be honest about the results.

K2
 
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