I currently load 3.5 grains of 231 behind 147 grain Berry's bullets, and have loaded 3.4 grains of 231 behind 147 grain Black Bullet International, as well as 147 grain cast bullets and had excellent results with all three bullets. These loads all functioned well and gave good accuracy in a Caspian 1911, a STI Trojan and a Springfield XD. I don't believe the powder is the problem, but if you want to eliminate the powder as a variable, let me suggest trying WSF (Winchester Super Field).