Thread: Adapting rimfire suppressor for .38 special...

The principal requirement of a suppressor is for it to have enough internal volume to contain and dissipate the gases produced. The gases are proportional to the amount of powder burned. A .38 Special cartridge would have at least four times more powder than a .22 LR, therefore you would need a suppressor with four times the internal volume to be effective. You could drill out a .22 suppressor to suit and it would reduce the sound a little bit, subject to staying in one piece, but the standard 1/2" UNF thread is not suitable for the .38 as the barrel wall would be too thin to be reliable.

Originally Posted by gundoc

The principal requirement of a suppressor is for it to have enough internal volume to contain and dissipate the gases produced. The gases are proportional to the amount of powder burned. A .38 Special cartridge would have at least four times more powder than a .22 LR, therefore you would need a suppressor with four times the internal volume to be effective. You could drill out a .22 suppressor to suit and it would reduce the sound a little bit, subject to staying in one piece, but the standard 1/2" UNF thread is not suitable for the .38 as the barrel wall would be too thin to be reliable.

That makes a lot of sense good point. I've found a 1/2 x28 .22 supressor which is the same factory thread as on my .357 rifle.