JScott.I shot a cull doe with a 220 MK out of my 300 Ultra mag at 31 yard's.My velocity was at 3058fps.The bullet broke one rib going in and broke three going out.The exit hole was somewhere between a tennis ball and a softball..Darry Cassel on this forum use them in his carry gun's.....He might be able to help you out more.I would however try the 168's out of your RUM....That 7 Rum is ONE BAD S.O.B.....I have an 7 stw that I'm thinking about having rechambered to 7 RUM....Darryl are you out there??????
