Concentricity

[BluntForceTrauma]

Ran across an article about Service Rifle competition and, interestingly, the author was very much convinced that match bullet loadings can be damaged on their way from the magazine to the chamber. You can read the article HERE, but I'm also quoting at length below:

"The loading/chambering cycle of the AR-15 is, in a word, violent. You have a relatively heavy bolt and carrier assembly under power of a stout buffer spring slamming forward to chamber each round of ammunition. By design, those rounds were supposed to be held securely by the magazine feed lips until the bolt stripped them off the follower. Obviously, due to their overall length, 600-yard loads can’t be chambered that way. Although the barrel extension is funnel-shaped, it’s also got a lot of “teeth” ringing the inside of it.

"Whether you’re using a standard magazine or a single-round loading device (SLED), dropping a round in the loading port and releasing the bolt is an act of faith in that you’re trusting the bullet to arrive in the chamber undamaged.

"Ask yourself, how many times have you seen someone drop a round on the follower, press the bolt release and watch as the bolt jammed on a cockeyed round? If that happens once every 100 tries, how many times did the bolt close on a scratched, dented, or misaligned bullet? Could that be the cause of the occasional errant shot?

"My technique is to drop each round on top of the SLED and then push it slightly forward with my finger, partially chambering it before releasing the bolt. Admittedly, some people may be unable to do this due to body configuration or left-handedness, but why go to all the trouble of loading “perfect” ammunition and then damage it on the way into the chamber?"