Screwtop.243
Ouch...that thing kicks
Hi Guys,
Well, my OCW testing session ended up good for the .25-06, producing a nice .36 MOA group out of my Cooper JGR with the 87 grain Hornady SP (#2530) and I've settled on a 56.6 grain charge of RL-19 for my groundhog season. Anyway, I found another box of those discontinued 87 grain boolits and decided to load up 30 more rounds to get everything calibrated out to distance with my Strelok Pro App. I finished off what was left of one box of boolits (10) and transitioned over to the other box, only to find a .007" discrepancy on the seating depth to ogive measurement between projectiles from the 2 boxes (using the Hornady bullet comparator). I typically seat them at 2.685" (ogive) .020 off the lands, but the newer pills, when seated with the same die setting are at 2.692". COL on rounds loaded with the second "lot" of boolits is also correspondingly .007" longer. I also measured the actual bullet length from both boxes and they are consistent at .893", so all I can think of is that the later set of boolits has a wider ogive profile closer to the meplat.
I'm trying to decide if I should leave the later group alone (now .013" off the lands) or just adjust the die and seat them .007" deeper, end result being a consistent "jump" to the lands (.020") but more possibly more neck tension on the later group due to more bearing surface contact? Which would affect accuracy more?
Thanks,
ST.243
Well, my OCW testing session ended up good for the .25-06, producing a nice .36 MOA group out of my Cooper JGR with the 87 grain Hornady SP (#2530) and I've settled on a 56.6 grain charge of RL-19 for my groundhog season. Anyway, I found another box of those discontinued 87 grain boolits and decided to load up 30 more rounds to get everything calibrated out to distance with my Strelok Pro App. I finished off what was left of one box of boolits (10) and transitioned over to the other box, only to find a .007" discrepancy on the seating depth to ogive measurement between projectiles from the 2 boxes (using the Hornady bullet comparator). I typically seat them at 2.685" (ogive) .020 off the lands, but the newer pills, when seated with the same die setting are at 2.692". COL on rounds loaded with the second "lot" of boolits is also correspondingly .007" longer. I also measured the actual bullet length from both boxes and they are consistent at .893", so all I can think of is that the later set of boolits has a wider ogive profile closer to the meplat.
I'm trying to decide if I should leave the later group alone (now .013" off the lands) or just adjust the die and seat them .007" deeper, end result being a consistent "jump" to the lands (.020") but more possibly more neck tension on the later group due to more bearing surface contact? Which would affect accuracy more?
Thanks,
ST.243