Hot Air?

Not a troll, not a sock puppet, just a first timer. I submitted a question for Cecil and was referred to the SDMB. I heard that a regular balloon put over the end of a gun barrel would act as a silencer. The reasoning was that the escaping air would be slowed. Is there any basis in fact?

Possibly. Supressors - no such thing as a silencer - mostly work by dispersing the sharp blast of gas that comes out of the muzzle. I’m not sure if the balloon is an UL but the BATF considers a plastic bottle attached to a barrel being fired to be a supressor, subject to severe criminal penalties if it isn’t registered and doesn’t carry the appropriate tax stamp.

Welcome to SDMB Sn-man. I hope you enjoy our company and stick around a while.

Nope, a balloon won’t work. But a potato will, or a foam pillow. But you have to do two things: control the sound of the exploding gases and keep the velocity of the projectile below the speed of sound. If you accomplish that, the weapon will be almost completly silent. In the case of semi-auto pistols, the only thing you can hear is the ejection/reloading cycle of the slide. Even good suppressors only last a very limited time though, before they need to be rebuilt. Several magazines of sub-sonic through an MP-5 are enough to wear a suppressor out.

The stuff with the potato or pillow I mean?

I thought it was insanely easy to get too much back pressure in a gun causing the breach and/or barrel to explode.

I.e. Take a rifle, poke the barrel in the dirt to get a bit if a plug and FOOM! I also heard, don’t know if it’s true, that sticking your finger in a barrel would be enough to cause the gun to explode (if the trigger was pulled…and it probably goes without saying that your finger will be pretty much gone if you do this). Of course, you’d need some brass balls to stick your finger in a gun that’s pointed at you but if it’s a choice between your head or your finger what would you choose?

If you didn’t know what you were doing couldn’t a potato do the same thing?

You answered your own question, but I will make sense out of a senseless world. If you plug up a barrel with mud or anything else, you will get an explosion if you try to fire a round through it. Once the projectile leaves the barrel however, the explosion menace is over. A potato, touching the end of the barrel, will not impede the bullet at all but will absorb the powder noise. Neither will a pillow, except that some types of foam will catch fire if you shoot through them.

Another way to do this which is almost as effective, is to use sub-velocity ammo and place the barrel directly against the target. Just below the skull in the rear with a .22 Walther semi-auto firing ‘shorts’ is the de-facto trademark of…(some countries)…, but almost anywhere against the skin will cause the powder blast to be absorbed in the body.

I can tell you who the best suppressor manufacturers are, or you can learn to make your own by reading The Anarchist’s Cookbook if it is still in print. Either way you are probably going to jail for a long time.

Thanks for the info. I am amazed at the uses found for the humble “Tater”.

US Army Green Berets, for one…“They don’t fall foward or backward…just kinda melt straight down.”–ex-GB on that method.

Not true unless you build or own an unregistered supressor or they are prohibited by your state. As long as you jump through the ATF’s hoops, the FBI background check and pony up $200 for the tax stamp it’s perfectly legal to make, own and use a supressor for otherwise legal purposes. Hunting with a supressor is illegal in pretty much every state and last time I checked murder was illegal even without one.

I saw something in a documentary about mistakes in forensic science that related to this… (VERY SQUEAMISH READERS STOP HERE…)

They described this one case where a woman committed suicide, but the coroner had originally thought she was shot by her husband because it seemed the smaller entrance wound was in her back. It turns out the larger wound in her stomach was actually the entrance wound. Apparently, if the gun is held tightly enough against the skin, the expanding gases from the barrel follow the bullet into the newly created hole, ripping the wound open. The gun itself did not appear to be damaged.

If memory serves, the gas pressure inside the barrel upon firing is somewhere in the neighborhood of 20,000 PSI. Sticking your finger all the way into a rifle or pistol barrel would likely explode the gun and your hand. Anyone who’s seen a fired bullet knows how deformed they get when they hit anything, and if it gets stuck in the barrel, the 20,000 PSI pushes out elsewhere, namely the weakest parts of the enclosed space. However, your finger would have to be small enough to fit in the barrel. My little finger is more than half an inch wide and could only fit the tip in a .44; I doubt it would work if I were insane and tried it.

I can only guess what pellets from a shotgun would do if plugged by a finger, but I suppose with the wadding, it would generally tend to explode the gun in the same fashion as a rifle. I would expect that it might take less backforce with a shotgun, as the barrel typically has a much thinner wall than a rifle. And since shotguns are more powerful as point blank range, there’s a good chance it would still kill you anyway.

But, based on the suicide above, I don’t think holding your finger tightly over the end of the barrel would have any effect (on the gun that is). If you are indeed close enough to stick your finger in the gun, you’d be better off pushing the point of the gun away from you. Or give whoever it is what they want if you care to live.