Kind of off beat can question

[Bartholomew Roberts]

Just a nonj-engineering type hypothesizing; but there are a couple of things causing noise when we fire a firearm - action noise (the mechanical parts of the gun cycling), muzzle noise (gases traveling at high pressures and supersonic speeds escaping the end of the muzzle) and bullet noise (the tiny supersonic wave that accompanies a bullet).

A suppressor typically only affects muzzle noise and does so by delaying the exit of muzzle gases so that the gases become trapped and have time to cool. The gases exit the muzzle at much lower speeds/pressures and reduce muzzle noise.

Now a 2-liter soda bottle isn't going to solve action or bullet noise. I doubt it will solve muzzle noise on a .30-06 since the volume of heated, high pressure gas should be more than enough to instantly rupture the plastic 2-liter bottle (don't see too many suppressors made of plastic do you?) and allow the gas to escape while still heated and at high pressure rather than trapping it and allowing it to cool.

So to the extent you saw any sound reduction, it would probably come from whatever extent the pressure was allowed to drop in the fraction of a second before the escaping gas ripped a hole in the side of the pop bottle.

Now a smaller caliber with less gas volume, say a rimfire cartridge of some sort - that might be doable, though I doubt anyone would mistake the noise for something other than a gunshot.

 

[gyvel]

To the best of my knowledge, the plastic pop bottle on the end of the barrel is more or less an urban myth; It's effectiveness is minimal. Of course, there were companies that took advantage of this and marketed the above-mentioned "adaptors" a while back.

But, there were also those among us who believed that smoking banana peels would get you high, too...

 

[PTK]

To the best of my knowledge, the plastic pop bottle on the end of the barrel is more or less an urban myth; It's effectiveness is minimal.

With water as an ablative medium and packing of any type (sponge cloth, in the case I heard) with care taken to preserve a clear bore, you would be SHOCKED how well a simple plastic bottle works on a .22lr rifle using subsonics. I know I was surprised - it was as quiet as my Tac-63 silencer. All I heard was the firing pin strike and the bullet hit the target.

Of course, I'd rather do things legally and have a metal silencer.