Pick a 158 gr. bullet, RN, RNFP, SWC, or TCFP and a powder such as Bullesye, HP-38, or Winchester 231 and start at the minimun charge and work up in .2 gr. (2/10gr.) increments and test fire each batch until you reach your desired point of impact.
The minimum charge should put your groups high, and come down as the charge increases.
Bob Wright