I have been reloading for amount 8-10 years and I have also used OAL per manual for regular ammo (for my open ammo, I usual follow you guys on forum as starter and see what works in my pistols) but recently, one of the guys that I know and respect told me he measures the depth of the projectile in the case and uses that are guide - INTERESTING..... It made sense to me when he said it....
So question to group, OAL or projectile depth in case?
I did notice that same projectiles from same company, different batch numbers, the round nose profile can vary and gives me SLIGHTLY different OAL - all plated RN....