View Single Post
Old January 16, 2013, 03:18 PM   #7
Join Date: March 4, 2005
Location: Ohio
Posts: 11,541
I would do it under two circumstances: The first is either of two conditions: A random 15 case sample of a mixture of years had more than 16% bigger standard deviation than a random 15 case sample of same-year cases. Or, if 15 case random samples of two different years had averages more than about a grain and a half different from one another.

The second is if the two case years represented brass with different load histories. A case that's been reloaded more times than another will tend to have stiffer neck brass from the additional work hardening (until it is annealed again). I want consistent bullet pull to help keep start pressure the same.
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member
Unclenick is offline  
Page generated in 0.07199 seconds with 7 queries