As a current M-16A2 toter (though modded), my vote is no dude. I have been playing with the M-16A2, the A4, and the M4 transformers, for years (mine were Colts and FNs if that helps either) and fired copious k's of rounds. The AR design is well, adequate. They are accurate and I've found them to be reliable in everything but sandstorms (KEEP THE DUST COVER CLOSED).
However, the 1/7 twist and 5.56mm ARE a problem, unless you are ONLY making holes in paper. The 1/7 twist causes for an over stabilization of the 5.56, this actually prevents the round from tumbling. Combine this with the fact that the 5.56 has a 3k fps Vel, and you end up with a penetration round NOT a knock down. The 5.56 also runs out of steam significantly at range as well...
My vote, not knowing your specific intentions, is this. Go with the 6.8mm SPC and go with another design, there are many other designs out there that are similar in price to the AR. Personally I like the Bushmaster ACR.
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