[yardie]

I'd say it's a hobby. Bullets are expensive in quantity. A full automatic can chew through $100 worth in just a minute. There are a few gun ranges near me that keep them available to rent. You can relive your A-Team / CoD dreams for a few hundred dollars.

Outside of the military they have no utility whatsoever.

[hansthehorse]

Full auto on an M16/AR15 will empty a 30 round magazine in a touch over 3 seconds. A few ranges near me will rent you a full auto AR but you have buy the ammunition from them.