9 major - determining OAL

[tcazes]

I know a guy running 124mgs and autocomp at factory length so roughly 1.13-4

I had my barrel fit and throated based on my 1.168-70 dummy rounds I provided. Your easiest and best bet is to make ammo that runs in your mags reliably (I run supers with no spacers and 1.168-70 runs 100%) and have the barrel throated to accommodate your rounds.

[rustybayonet]

What I did to find max oal for a firearm, was to take a properly size case cut it lenght wise on one side. You can then seat a bullet high. Chamber it, it has enough give to push the bullet into the case at max oal for the chamber. I would drop it down a hair so your not sitting on the rifling. Then measure. After that you can use that same test round for function and mag fit. And the bullet comes out ez for the next test.