[VARMINT223]

I use factory ammo as the baseline for my reloads. If the factory ammo cycles for me, I use those dimensions. I usually find factory OAL shorter than that specified in the reload manuals for my 9mm and .45ACP (SAMMI). I would treat LRN and FMJ-RN the same.

 

[VARMINT223]

Ok, So now what about the pressures as the OAL is shortened?

I mean at 1.169" the 115GR bullet is hardly in the case. It seems quite long. Most of the 9MM i've ever purchased has a way shorter OAL.

I'm confused here. Wouldn't shortening the OAL increase pressure quickly?

I'm thinking about what you wrote.

In the past for my Sigs 9mm and Springfield 1911's, as loaded per Speer/Hornady reloading books which I have to believe are SAMMI based. At those COAL, the cartridges cocked and jammed in my mags. So I measured factory ammo that worked.

Never any problems w/flat primers or signs of overload. As a rule of thumb I never push my powder loads past 80% maximum.