Sen. Coburn on the M4
Senator Coburn raises questions about the M4 rifle.
I've no experience with one. I know that its predecessor, the M-16, had serious jamming problems in Vietnam, and I've read reports of jamming in Iraq, but no idea whether those were common or rare. While I do an AR-15 type firearm, and like it, I've always been a bit suspicious of direct gas impingement, esp. in a setting where you might have to fire off hundreds of rounds without cleaning. Might any readers have experience, or know of those with it, in this area?
UPDATE: I'd agree the cartridge is a big problem -- and least likely to be fixed soon. Changing over is a major operation (and requires coordination with NATO). Consider that in 102 years, we've only switched twice -- from .30-06 to .308, a modest change after nearly half a century, and then to 5.56mm (with lots of .308 weapons still in use).
I was involved in the Waco civil trials, and one exhibit was a revolver carried by an agent as backup. It took a hit square on the sideplate while he wore it, from an AR-15, with the old 55 grain projectile. It blew a star-shaped crater in the sideplate, a little over a half inch in diameter and maybe an eighth of an inch deep. The revolver was probably still usable. The hit knocked him down, he got up and was moving again without injury. You wouldn't see that with a .308. Of course they've switched to a heavier round with a steel penetrator tip, but that just gives a tradeoff. More penetration, but less stopping power. You can use your limited energy and momentum one way or the other.
ANOTHER UPDATE: the problem with Vietnam M-16s was the lack of a chromed chamber, and also a switch in propellant. The rifle was originally tested with tubular powder. Then they went to ball powder. As I recall the issue, the ball powder had more retardent, and thus more fouling. Jams became so frequent that they added the bolt assist to force a jamming round into the chamber (as one user remarked, how come Kalashnikov never had to add this sort of thing to the AK?)/