When I first got my Tikka 300wsm, it was a new caliber and there was very little load data. So I took what published load data there was and using powder burn rate charts, began building my own loads. I pushed mine for high velocities adding one grain at a time expecting bolt pressure before going too far overboard. I did get as high as 3400 fps out of 150 gr bullets with little pressure signs and good accuracy. Then one day, without warning, I blew a primer out the back of the bolt which busted off the bolt shroud. I'm lucky to still have vision in both my eyes. I backed off the pushing the limit for mach-speed velocity. Now there are plenty of recipies available so I stay very close to published loads now. I do however suspect that with the tight tolerances of the Tikka rifles, they might not always show the pressure signs that other rifles do.
