300 win mag reloading issues

Nagol

Private
Minuteman
Feb 9, 2020
2
0
Hello I am reloading for 300 win mag and with new brass I can shoot 4 shots in one hole and my fired brass after resizing just doesn't shoot well. So looking at my cb to ogive on fired brass it seems to vary so how can I consistently just bump the shoulder back 2 thousands should I just discard all brass that doesn't have the same numbers? Also the trim to length is 2.610 is it okay to trim to say 2.608 ? Does anyone shoot norma brass I just ordered some and want to know what bushing to use for 2 thousands neck tension? I have not been able to find much info about this your experience would help me a bunch thanks sniper's hide community.
 
I’m on third firing of Norma brass in a hunting rifle and settled on the .333 neck die with a button bushing. I have notes that say .334 seated real easy and I also messed around with the .332 and a mandrel.

New brass shoulder started about 2.205 and went to 2.220 after firing which is shorter than the dummy round provided by my builder so I haven’t been bumping back any significant amount. Are your rounds difficult to chamber without a shoulder bump? You might not need any.