A suppressor, in the context
, is a device which is used to (surprise) suppress the sound and light produced by firing the weapon. This is typically known as a silencer
; it focuses on maximal
noise reduction. A flash suppressor
is intended to reduce the visible results of a shot, although this will do that to some degree as well. It will degrade under use; it therefore is best used on single-shot
As a side note, it is not possible to silence a submachine gun. The devices shown in the movies on submachine guns are suppressors, and they do not silence the weapon, but merely reduce the report. Note that even if you muffled the shot itself, the weapon's action would be quite loud; much of the noise of an AK-47 is in fact the action cycling.
Warning! Suppressors are ILLEGAL and more to the point dangerous. DO NOT TRY THIS. The following is for informational purposes only, and will LIKELY GET YOU SEVERELY INJURED OR KILLED IF YOU TRY IT, unless you're a professional gunsmith, in which case a) you already know it and b) you should know better.
The design of a suppressor varies according to the manufacturer, but the basics are common. Essentially, to make a suppressor, take a large can
-shaped cylinder of metal. At each end weld a disc of metal to create a 'top' and bottom' - also do the same several times spaced through the cylinder. Viewed from the side, in cutaway, it should look like a cylindrical
building, with 'floors.' (Obviously the easiest way to do this is to build the can in halves, weld the discs into one half, and then re-close it).
Next, create a mounting point. At one end of the 'can', make sure there is a disc within a centimeter or so of the endcap. Make sure that the discs are sturdy enough to be used for mounting points; if not, add some more between the two. In the precise center of the end of the can, drill a hole which is slightly smaller than the external diameter of your firearm's barrel at the muzzle.
Once you've done that, use a tap and die to create a matching thread on the outside of the end of the gun barrel and the interior surface of the hole so that you can 'screw' the suppressor onto the end of the barrel. Remove the suppressor again.
Now, through the exact middle (and believe me, accuracy is important!) of the suppressor, in line with the mounting hole, drill a pathway that is perhaps one or two hundredths of an inch wider than your bullet caliber. For safety's sake, you may wish to widen the holes a caliber or two per disc to allow for tumbling of the bullet. Bingo - your basic suppressor.
The theory is that when the weapon is fired, the bullet will travel out the muzzle and down the line of holes in the suppressor. As it does so, it will 'open' each baffle (area between two discs) to the escaping gases behind it. The gases, given a much wider area to expand into, will divert much of their energy to expanding outward into the open space while the bullet continues on. Thus, the characteristic bang of a gunshot (the escaping gas) will be muffled as the energy that would normally create this wavefront is instead sequentially dispersed in the baffles.
Now, the most important means of quieting your weapon is not part of the suppressor, but without it, the suppressor is pointless. One of the loudest parts of a gunshot is the crack of the bullet breaking the sound barrier. To avert this, use subsonic ammunition! Most 9mm handgun/submachine ammo, for example, is supersonic; you'll need a downloaded cartridge.
Of course, there are innumerable ways to improve on this design. If you only intend it to last for a few shots, you can pack the baffles (the open spaces between the discs) with wadding or foam to further absorb the gas energy. If you're brave, you can mill the holes in the discs as close as possible to the diameter of the bullet and hope like hell you got it on straight. You could experiment with drilling small holes in the outside of the suppressor to allow the gas pressure to bleed sideways in tiny jets, further reducing the unity and power of the shockwave. Rubberizing or otherwise softening the internal surfaces of the baffles would naturally help as well.
What will this get you? It will (probably) serve to dramatically reduce the size of the bright cloud of hot gas that your weapon emits behind the bullet. This will reduce your profile, as well as likely preserve more of your night vision. It will reduce sound, making your activities less likely to bring hordes of nearby listeners. On the other hand, it will be awkward, fragile, and dangerous if damaged. It will reduce the energy of the shot somewhat. The turbulence of gas escaping around the bullet, which normally only occurs once as the bullet leaves the muzzle, will happen once per disc; the result will be decreased stability and accuracy.
Why would you use this? Other than the obvious means of shooting people without attracting attention, if you intend on being in a firefight at night, you will likely improve your chances of survival since you'll be harder to see. Hunters, as well, might benefit from rifle suppressors so that in case of a miss, the sound of the shot doesn't spook an entire area. This is what the world's first suppressor - called the 'Dr. SHUSH!' - was made for; however, it really seems (to me) to be highly unsporting.