.260 SAAMI max - 60k psi 6.5x55 SAAMI max - 51k psi 6.5 Creedmoor SAAMI max - 62k psi
H414 has been such an easy and resilient powder in several other cartridges that I once tried a load in my 6.5 Swede that created a primer pocket I might have seated a 50 BMG primer in afterward. I'm thinking that load was 'a bit' over 51K anything.
Sometimes, the air you 'let in'matters less than the air you 'let out'.
