How much, or how little, does it take?
MANY years ago I bought an M1 carbine together with some ex-military ammunition and a full set of reloading equipment to utilise a hard cast lead bullet with gas check. The carbine was surprisingly accurate with the GI ammunition giving me 7cm groups at 100m. I confidently prepared a batch of 20 reloads but was horrified when the gun blew up with the first round I fired. I took the M1 to a gunsmith with the rest of the reloads. We both assumed that I had overloaded with powder or used incorrect powder. However, it was found that the problem was caused by the sizing dies being incorrect. They were .313 not .308. Using lead bullets, I would not have thought that being 0.005 oversize would be so catastrophic. Luckily the gunsmith who sold me the incorrect die replaced the M1 with another.
A similar problem occurred when I was loading some
