A&K FN LICENSED M249 MK1 WITH BOX MAG
FN HERSTAL M249 MK1 is an awesome full metal support gun which comes with a lot of kit for your money!
Firing at around 340fps, it comes complete with a 2500rd box magazine which will auto-wind when it detects the sound difference as you dry fire a couple of rounds. It can also be switched to continuous wind if required. You can also use standard M4 magazines in place of the box mag for extra realism and heart pounding quick mag changes as this beast will chew through your ammo at 1400RPM!