Steve, I've been following your 325 WSM thread postings and your Winchester 70 Extreme Weather thread with great interest. Congratulations on your hunting successes!
I've been thinking about getting a 325 although I certainly don't need it. I have the 70 Extreme in 270 WSM and the Coyote Lite in 243. I always enjoy seeing how someone who really knows what they are doing goes about load development, and especially the great results you have shown.
I spent quite a bit of time over the last year developing loads for these, mostly for the 243. My old 70 fwt 270 WIN from 1955 still shoots a jagged hole with almost any load, but my new Winchesters were all over the place (1 1/2" best). After probably 300 or so test loads, including shoot-clean, the 243 is now very consistent well under 1". I even shot a .33 group sitting in the snow off my shooting sticks just before a coyote hunt in Maine, and a lot of .5 - .6 groups. I mostly concentrated on the 243 for coyote hunting but did a little work on the 270WSM and finally got several 1/2" groups. I'm certainly pleased with both of these. I just love these new M70's.
It the time I never had the OAL gauge so seated the bullets by trial until the bolt just closed freely, then measured them and set them back 0.005 additional. One of the bullets in the 270 was a Speer 130 SP. Yesterday I attempted to establish the max length using the Hornady overall length gauge and what I found was that my former method has the bullets seated about 0.005 longer than the max length, NOT 0.005 shorter.
My guess is that the bolt closing method can force the bullet much farther into the rifling than the lock-n-load gauge, even though you can't feel anything, and I can't see any markings on the bullets.
I like the idea of being able to measure this dimension but want to make sure I'm doing it correctly and have measured the correct max overall length.
I tried to follow the instructions but not sure. I first set the bullet deep into the case, then very firmly seated the case into the chamber. I then very firmly pushed the bullet as far as it would go and tightened the set-screw. I never pounded it with anything, just a very firm push. The bullet stuck in the rifling and I pushed it out with a dowel. I repeated it several times and go the same value.
Any Ideas? Am I going about this correctly?