PPC neck tension

N

Norman Maxwell

Guest
All: I keep 15 cases at a time in my loading block while at the range. 2-3 cases seat the bullets "too easily" compared to the rest of the cases. this is after several firings. Is the solution a smaller bushing, or is there a brass preparation step missed that causes this? I keep the same bunch of cases together from the time I take them out of the box (Lapua) Thanks.
 
I turn the necks myself, and check each with a ball mic. Thanks
 
Check each round with a bullet seated and measure with a good mic that reads to .0001" See if there is any variation in the diameter this way. This is more accurate than the ball mic. The error with the ball mic could be a .0001" or 2 and then multiply this by 2. It can add up to a .0005" real fast. Also, how many times have these cases been fired?

Joe
 
On cases that have been fired several times and that were sized with light neck tension, say 0.258 bushing on 0.260 finished necks, you will feel quite a bit of neck seating variation because all cases don't spring back the same.

On cases that have been fired several times go to 0.257 or 0.256 bushing. But, too much neck tension will cause variations in seating depth though since the neck will spring some during seating in a tight press fit.
 
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