TR, the fact that the action noises come very clear is quite common with AR15/M16 series weapons, even the spring noise in the buffer tube comes quite clear.
The fact that a quality suppressor made with current suppressor technoloy, suppresses the SPL by around 27-35 dB, causes the action noises to come more evident to the shooter. An M4 unsuppressed is around 163-165 at the muzzle.
For reference, here is a brief clip, the weapon is a BM M4 with a 14.5" barrel, with one of our suppressors. Of course the true nature of the sound doesnt come away quite as it does in the real life but one can see a clear differene though.
http://www.aseutra.fi/english/product/AU.wmv
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