Ive worked up some Seneca's for 6.5 creedmoor and ended having to load them at 2.932" to shot .5 MOA groups, and they wont feed from a standard aics mag. i found the lands by painting the pilot band of the projectile and using a hornady comparator to measure the overall length, i added the length of the mark and called that case ogive length if it were touching the lands, I worked back from there in .005" increments for 10 groups of 5 rounds. first target is the charge weight test and the second is the seating depth test (left column bottom paster 2.932" .51MOA).