well actually a form 1 which is what he will have to fill out to own it calls it a suppressor or muffler.... you should know that having a 16" barrel is a disadvantage to getting a gun quiet..
hv ammo will break the S.B. and you will hear the sonic boom which is almost as loud as a 22 rifle... you will have to shoot sub sonic ammo to get the effect your looking for.. we just got a yhm maxim 22 suppressor, came in yesterday that belongs to john personally.. (about 4 months turn around on the batf tax stamp) and its quiet and is offset so you can put it on a pistol and still see your sights..

you may wanna look at a few heads up comps. of the tac65 and others they are not as quiet as some of the others.. but if your never standing next 2 of them youll never know...

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07/SOT2
NRA Instructor