I just ordered a RCBS rock chucker supreme kit from midway usa. I went ahead and ordered die sets for my 300wsm, .260, and .44mag. So if anyone has any advice or favortie loads pass them on if your willing.
I woulld suggest you try to get a powder that you could us in both the 300 WSM and 260 to get started with,IMR 4064 is real good in the WSM with 150gr bullets,no ideal on the 260. H110/W296 for the 44Mag.
I have very good perfomance with 140 gr Hornady Interlock with 42.0 gr IMR4350. I also tried the 120 gr NBT with 35.0 gr Accurate XMR4064. I haven't finished adjusting that load yet. For plinking and coyotes I shoot 85 gr Sierra HP with 42.0 gr XMR 4064.
My rifle has a 16.5 in barrel and the max loads don't get much more velocity than slightly less powder, so I believe these are all less than published max loads.