135 SMK's in a 308

Re: 135 SMK's in a 308

Just put together a few rounds with this bullet in my CZ550 varmint using IMR4064. I called Sierra for the loading range (41.5 - 49.7) and they recommended 47.0 - 47.5gr for best accuracy. They were pretty close. 47.9gr with CCI250 primers and Federal cases gave me .5" groups and an ES of 3fps. Velocity was right at 3000fps. The groups opened up and the ES increased predictably as I went to the max charge weight. My barrel twist is 1:12.