Originally Posted by Ludicrous
I just have a hard time using the longest measurement. Example ( and it usually is about this way) I fire 50 and have 40 in stack "a", 8 short in stack "b" and 2 long in stack "c". I'll remeasure a few times and even use a second caliper. I can understand how some cases can be shorter but not the "longer than the chamber" ones. Maybe it's because we cam the bolt open quickly and eject them real hot. Who knows. You've shot thousands or hundreds of rounds in your rifle and know that measurement but a few long ones always pop up.
keep this in mind:
* unless every loading is identical right down to barrel fouling; you'll see some difference.
* brass will vary from lot to lot (material not cases). This not just the brand name, but from one lot of ingots to the next lot. Ideally we'd have cases from the same cupola and the same pour, But that's a rare thing.
* assuming your cases are all the same brand, and were from similar lots; then maybe it's time to anneal all the cases.