Marui M14 Socom stock resonance while firing
 

My stock Marui M14 Socom has always produced an annoying noise, a kind of resonance insice the stock every time I shot a bb. maybe due to the proximity of the gear box and motor
Anyone has experienced this? I wish to try to put some foam inside the stock to reduce resonance.

it's probably an echo from the battery compartment in the back of the stock, though the mid and front of it has lots of voids inside... you can try dynamat... that stuff they use in cars to dampen stereo vibrations and road noise, but you have to get inside to lay it and stick it.

For the front of the stock, take it all apart and pump it full of spray foam maybe.

It is only in the back of the stock , strange thing this Dymamat, I didn't know about it