Congrats...Good for him! That rifle replaces the CVA Staghorn 209. Shoots best with moderate powder charges 80-110 Pyrodex equivalent loose). Best sabot/bullet grain size are from 240-300 grains. I'd guess to say a 240 gr T/C Cheapshot -- 300 gr. Hornady XTP or 250 gr. T/C Shockwave with 90 grains might be a good starter/finisher load. Hard to tell exactly because ML rifle bores vary gun-to-gun. Another bullet to try is the 348 gr Powerbelt.