AR-Stoner 6.5 Grendel barrel short chambered.

[LRRPF52]

I just measured a box of 123gr factory Hornady A-MAX for raw COL. Every cartridge was 2.250"-2.252". The ogive might be slightly different than the SST though, since I am able to load the 123gr A-MAX longer than the SST.

I made a dummy 123gr SST round, and tried it in my AA barrel, as well as a Satern 18" Grendel barrel. I can load it to 2.253" where it will just kiss the forcing cone. It chambers and extracts without force.

I also tested my long-loaded 123gr A-MAX in the Satern chamber, and no issues...chambers and extracts without force. That's a 123gr A-MAX at 2.275".