I worked up to 81.0 grns of IMR4350 with 270 gun TSX bullets which is a highly compressed load but didn't see any pressure signs. Accuracy wasn't as good so I went back to 79.0 grns. I'm not sure if a 270 TXS is as long as a 300 A-Frame.
I tried R-15 and got better velocity, but accuracy suffered. My rifle just likes IMR4350.
