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How Much Variation In OAL Is Normal?

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February 14, 2018, 01:30 AM
Jager
How Much Variation In OAL Is Normal?
Using 9mm copper jacketed or plated bullets on the 550B (I don't load lead in 9mm, only 45 ACP), I thought .003-.005 variation was driving me nuts!

I separate all brass by headstamp for my ammunition. Brings the variation down considerably. Oddball headstamps in 9mm get tossed. IOW, if I have less than about 200 of a headstamp, I have no use for it. 9mm is up to 35,000 cup. I refuse to play.

The 'deviated' ones get separated from the 'intended' ones (yes, I measure every one of them) and I use those for informal plinking.

.016? I'd be thinking my press had worn out parts or something.

In 45 ACP, I load batches of the same headstamp and use jacketed, plated and moly coated lead bullets. Oddball 45 ACP cases I WILL load, but they are identified as "Misc Brass" loads and are used for informal plinking. 21,000 cup has much more wiggle room.

My personal goal for accuracy is all rounds offhand within a 3" circle at 12 paces. The range has a 40' line, so close enough.