ffg 777 is probably not 15% stronger than pyordex P. The 15% comparison is to pyrodex RS or to pellets. P is smaller grain and would be closer to 777 stength but I don't know how much closer

I assume you mean 30 gm BY VOLUME? If so, I agree that I would never feel comfortable shooting a deer, even one's as small as you describe, with that load. Certainly if you keep the distance to 20 yards or less you may be OK, but it would not be my cup or tea...