My Marlin rifle loves 13.0 grains of AA#9 with Hornady's 158gr FP/XTP bullet. The FP/XTP is designed for higher velocities from a rifle. I use RP brass and CCI 500 (not magnum) primers. The overall length of the loaded round is
1.580" This load comes from Accurate Arms data but it is not a starting charge. Start lower and work up to it. For your rifle I'd stay with Win 296, H110, AA#9, 2400, or Lil Gun powder. Don't even try Bullseye. When you consult loading manuals you'll get conflicting maximum charges. For instance Hornady says 11.5 grains of AA#9 is maximum using WSP Magnum primers while Accurate Arms manual #1 says 13 grains is max with CCI 500 primers, and Accurate Arms data available at their on-line site says the maximum with AA#9 using CCI 500 primers is more than 13 grains. Follow published data using the components specified. All I know is 13 grains of AA#9 shoots well in my rifle without any pressure signs.