I’m looking for something to drive a 105 grain bullet passed the supersonic threshold.
FortuneCookie45 used 4 grains of Universal to compare case efficiency: 38 Short Colt vs 38 Special. He got on average 350 FPS greater velocity from the 38 Short Colt brass. And amazingly he was using 158 grain bullets and averaged about 1075 FPS with them.
I’m thinking of starting with 4.5 grains of Titegroup.