Last winter I bought several hundred cases from my local enabler. Over time I have gotten around to full length resizing them, de-capping, chemical cleaning, tumbling and reaming out the primer pocket swage.
I was loading some this week and decided to check the case length. These are Lake City cases that I am sure were fired in some variant of the M-240 Machine gun. To size them with as little effort as possible, I soaked them in 2 cycle engine oil and mounted the Rock Chucker on a bench outside. It was messy but easier than using sprays or sizing wax. I had to use a pressure washer to get all the oil off the press, resizing die and bench.
Case lengths ranged from 2.008 to 2.041. I trimmed all of them to 2.008-2.009 with my new Lee crank handle trimmer (SAAMI standard is 2.015).
How could the OAL have such a range for once fired brass? Do different lots of brass flow/grow different from other lots?
Looking back on this project, if my time was worth minimum wage, it would have been cheaper to buy Lapua virgin brass.
(by the way, Lapua brass is selling at Midway $72.95 per hundred, which is cheaper than the Hornady match brass listed for sale there.)