From CWO4 Billy Atkins, USAR Rifle Team Captain (some years ago).....
The US Army Reserve and Nat'l Guard rifle teams tried reloading their M118 match and commercial .308 Win. cases fired in M14NM's. None of them shot as accurate as new cases. M14NM's never had their bolt faces squared up so fired cases from them had out of square case heads; some worse than others. No reloading process squares them up. You could shoot them loaded to 30% to 40% over safe max pressure (same as proof loads) and that would square them up quite a bit. The USN Team tried it and got the same results in 7.62 NATO Garands. One other service team tried it and forgot about it, but I don't remember which one it was.
You can see how much out of square case heads are. Stand them bottom down in the V of a steel square taped to a table top then spin the case holding the case head in the V so it spins on its axis. Watch the case mouth from straight over it. Set up a magnifying glass over the case mouth and it's easier to see. Square case heads let the case mouth sping on its axis. Out of square ones makes the case mouth spin about someplace off the center of the case mouth.
However, it is good for stuff where best accuracy ain't one of the objectives.
Last edited by Bart B.; September 5, 2012 at 06:33 PM.