in my Marlin 60 (same action I think) I shoot the CCI Mini Mags. It seems the Marlin guns do best with high velocity rounds. My gun also likes the 40 grain pills a lot more than the 32 and 36 grainers (stovepiping and jamming), but no problems with the 40 grainers. I have also shot the Win. Wildcats, but I don't know that they produce them anymore.