SACair Forum

I had just recently purchased a CA MP5SD3 and I was wondering if there was anyway to fill the silencer with foam and which kind should I use.

if you want to fill the silencer to "silence" it you will find that it won't do much since 90% of the sound comes from the gearbox itself and not from the muzzle.

I know the gearbox makes noise, but the "clap" sound after each bb exits is what i want to get rid of.

that is directly from your gearbox. It's the piston head slamming into your cylinder head. If you want to reduce that then I suggest looking into getting an Angel Silent Piston head. The Angel version is properly designed to reduce the impact sound unlike the Systema which does nothing. Also reduce your spring to an m100 or less, and keep your ROF down too.

that sounds like what I need to do, but my uncle has the P90 TR and with the silencer it actually reduces the noise. Is this just because of the TM build or is it because of the silencer.

it is due more to the build. The fact that plastic itself is more sound asorbant than metal and how the gearbox itself is designed. The silencer does muffle the exiting air but that isn't noticeable by anyone beyond 50ft. regardless.

alright thanks for the advice and clearing up my questions