"Don Foreman" wrote in message
...
I've read here that silencers are not compatible with revolvers.
The question of why that might be so has bugged me since I read it.
Why is that so? Does it have something to do with clearance between
cylinder (chamber) and barrel?

Yup, that's exactly what it has to do with. Remember that all sound is
simply pressure waves in an environmental medium (like air). The purpose of
a supressor (the correct term for a "silencer") is to take the
high-pressure, high-velocity gases at the muzzle (that are created by the
buring cartridge propellant), and simultaneiously reduce their pressure and
speed in a controlled manner to minimize the creation of sound pressure
waves in the air. It cannot do that if the burning gases are escaping to the
atmosphere at the cylinder gap.


How about rifles that are not gas-actuated semiautos, i.e. bolt,
lever or pump actions? Perhaps it's not feasible to effectively
suppress the report of a rifle with supersonic muzzle velocity,
which (I think) includes most modern centerfire rifles.

Any firearm with a completely enclosed chamber and barrel are good
candidates for suppressing with regards to minimizing the report from the
burning/expanding gases. Any manually actuated firearm will be inherently
quieter than an automatic or semi-automatic for two reasons: you minimize
the escaping of propellant gases; and you minimize the cycling sound from
the action. For example, there are suppressed Ruger 10/22 rifles where the
sound of the cycling semi-automatic action is louder than the muzzle report.
So, if the action was not semi-automatic, then that rifle would be even
quieter.

Yes, one does have to consider the sonic "crack" from supersonic velocity
bullets. But even if you fire supersonic rounds, the suppressor has value.
While won't be shooting silently, the benefits a

1. The supersonic "crack" alone does not sound quite like a normal gun shot,
so that might be confusing to some.
2. The supersonic crack is less localized, so it's more difficult to
determine the location of the shooter.
3. Sound volume decreases over distance in accordance with the
inverse-square law. So any reduction of sound is beneficial when the
listener is not nearby.

Regards,
Michael