Seating depth testing?

[daved20319]

So I've found what I think is a good node with Berger 144 gr. LR Hybrids and VV N555 powder. Good velocity, excellent SD, but mediocre accuracy, at best. Started with book data for OAL, but now I'm ready to see if seating depth makes this a "magic bullet" :cool:. I've already determined max length to the lands, question is, how far off do I start, and what sort of increments should I be using? Just in case it matters, I've been using 2.795", max in this rifle is ~2.910". Oh, and it's a 6.5 Creedmoor. Thanks, guys!

Dave

[Stumpkiller]

The rifle will tell you. I shoot a 0.264" but not that bullet or cartridge. With some 140 to 156 gr bullets it likes a jump of 0.015" to 0.025", but with my hunting load (260 Rem w/Sierra GC 130 gr VLD ogive) the happiest groups seemed to be at 0.060"(!) off the lands. And that is still 0.037" over the C.O.L. called for. Happily the Savage magazine/action is generous.

That's a seated depth of 0.573" and is a slightly compressed load with the base below the shoulder. Loooong bullets in one caliber necks.


I guess SAAMI hasn't caught up with secant ogives yet. ;-)