I also have a mountainer and have not had a lot of time to shoot it but from what little I have shot it it shoots the 350 grain FPB with 105 grains of BH 209 pretty well 2 1/2 inch group at 150 yards but that is with a 3X9 scope. I'm going to try barnes tmz in 290 grain when I get a chance. Hoping to close my groups under 2" at 150 yards. Good luck and keep us informed on what works best for ya.
