Picked up some 139gr IB for my 7mm RM and was wondering if anyone has experience with them in the RM and what powder(s) would be good to start with. Game will be whitetail deer.
For bullets from 139 to 162, H4831 has been my go to powder for decades in the 7 mag. Winchetser brass, CCI250 mag primer. Simple to develop loads, temp stable and great accuracy.
My preferred 7mmRM load is 154gr Interbond over RL 23 and it perform really well on whitetail. I think the 139gr will perform well too as the bonded core should hold up to the increased velocity. I bet you can get good performance with RL22, RL23 and H4831SC among others. What powders do you have available?