[lurkingknight]

there are 2 major sources of sound from an AEG, the gearbox cycle and the muzzle pop.

The suppressor WILL dampen the muzzle pop. The shooter may not hear it because his head is right beside the gearbox, but anyone downrange may not hear the shot or think it's pointed in another direction.

The larger diameter cans do a better job at this, provided that there's foam in the can and the inner barrel leaves a space between where the BB leaves the inner vs where it leaves the suppressor. The amount of gap may make a difference in the dynamics of how the sound travels and is broken up in the foam.