m4 ramps were just a con job so colt could get the no-bid contract.
the m4 ramps don't help longer rounds either cause if there that long--they won't fit in the mag so you don't need the ramps--LOL
sort of a tits on a bull thing.
hey j4 i had a rem. 7400 3006 that the ramps would actually shave off some of the bullet ramping in the chamber and jamb the thing up bad. the ramp to the chamber had a sharp edge and boy if you shot it more tan ten times would lock it up like hell. had to carry a lady finger brush to keep it cleaned out. what a bitch.