View Single Post
Old December 9, 2018, 01:43 PM   #8
Unclenick
Staff
 
Join Date: March 4, 2005
Location: Ohio
Posts: 16,980
Chainsaw,

Is there any chance this is a highly compressed load? Often, those will push a bullet back out.

If that's not the case, then the only explanations that occur to me are:
  • The seating die's little stem is not in the same place each time (remove the top plug and check for debris).
  • You aren't getting the press ram all the way up each time (you'd be surprised how common this is).
  • You've got some wrong bullets mixed into the box or are using cheap bullets for which lots have been mixed.
I once measured a sample of 15 Sierra 150-grain .308 MatchKings each from the base of the bullet to the ogive point of contact with a comparator and got an extreme spread of 0.008", or ±0.004" from the mean and a standard deviation of about 0.0025". So I would not be surprised to see as much as about 0.010".

The thing to start with is what I did there: Use your comparator to measure each bullet base-to-ogive length and make sure they don't span more than about 0.010". If they are OK, one of the other factors is involved. If they are not OK, you've got an issue with your bullet supplier or with a gremlin.
__________________
Gunsite Orange Hat Family Member
CMP Certified GSM Master Instructor
NRA Certified Rifle Instructor
NRA Benefactor Member and Golden Eagle
Unclenick is offline  
 
Page generated in 0.02695 seconds with 8 queries