The Hornady OAL gages are pretty easy to use. Start with a clean chamber if the cartridge headspaces on the shoulder. Ensure the case is well seated (I generally rotate mine clockwise while lightly pushing it towards the muzzle). When pushing the bullet forward, do so lightly and take 3-4 readings to ensure consistency.
You will find surprising differences in COL even when the OAL gage for loaded rounds is consistent.
Coyote Hunter - NRA Patriot Life, NRA Whittington Center Life, GOA, DAD - and I VOTE!
No, I'm not a Ruger bigot - just an unabashed fan of their revolvers, M77's and #1's.
A good .30-06 is a 99% solution.
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