What are you planning to hunt and at what range?
This info is for 175gr pills. I would start with Retumbo or R25 all have been good performers in my 300UM. I tested some 8700 last week 106gr behind a 220 MK and was pleased 3042fps out of a 26' tube.8 in groups @100.
A lot of guys like to load the light bullets in the 7RUM. I see no point in it. That 175gr Partition is the way to go if you ask me good BC and Superior SD= big penetration not to many critters that will stand up to that in NA. The 160gr slug would be as light as I would go with the RUM but that is just my option. Welcome to the board lots of knowledgeable people here. Good luck.
Retumbo From 86.0 grains to 91.5 grains
IMR-7828 From 71.6 grains to 80.5 grains
RL-25 From 76.3 grains to 88.6 grains
RL-22 From 71.7 grains to 80.6 grains
AA-8700 From 81.4 grains to 103.0 grains
H-1000 From 71.7 grains to 87.5 grains
H-4831 From 72.9 grains to 81.4 grains
