Use 85 grains Blackhorn 209.
Each of your 50gr 777 pellets contains 43gr of 777. It was dumbed-down years ago to meet the same strength of 50gr Pyrodex pellets. Was done that way for both safety reasons and convenience for shooters to mirror very similar target holes using these two differing constructed pellets.
Last edited by GoexBlackhorn; 12-10-2016 at 04:26 PM.