Wow, I go away for a few days and this has morphed into a very interesting science project. About the only thing I can add is regarding Weatherby factory ammo. On TWO separate occassions, I've had pressure problems with them. One with 180gr Barnes Xs (not TSXs) right before I went to Africa with popped primers and sticky bolts and the other with 7mm and the 139gr Hornadys at 3500 fps! Also, can one of you learned gentlemen confirm or deny that spherical (ball powder is more succeptible than extruded when it comes to hotter temps? Reason being, my best 375 H&H load is with H-414 and 300gr Swift A Frame handloads @ 22560 fps. No problems on two different Safaris in Africa where temps were around 110 at mid-day. Maybe as the ammo get older it cakes? jorge
