Squiddy wrote:Ok, so as far as I can tell from the wording of the legislation, technically shooting through a padded barrel is legal as it is not fixed or attached to the firearm anywhere?
I'd be interested in seeing what sort of noise reduction a unit like that actually provides, as most of the gas is still escaping the barrel quickly.
Agree with both statements, however it is how the gas escapes or rather what happens to the shock wave (sound) that modifies how it is perceived and results in a noise reduction.
Remember that no sound modifier reduces the resultant sound to zero. The perceived result depends on the level generated in the first place, size of the shock wave. In the case of a firearm the difference between say a .22 rimfire to that of a .308 centrefire.
In my view and looking at the designs of any of these they are the same as putting a muffler on a vehicle exhaust. The difference between an engine with no muffler. Ever been to a drag race where the exhaust is not muffled at all, the noise level is extremely high. Then a race car compared to your own, motor bikes with different exhaust muffler designs and the difference in noise levels.
The design of a Sound Modifier (Silencer) is the same basically as an automotive muffler, the drum with acoustic foam (pictured above), a line of tyres etc. Idea being that yes, the gas is still escaping the same but the single shock wave and path is broken up into smaller ones as well as the direction of that sound wave so the perceived overall noise level is much less.
A sound proof room, same idea and same result.