I shoot .40 cal, 200 grain XTPs in a .45 cal Kodiak using BH209 and have zero issues with it. I tried the .40 cal bullets in sabots in my v2 Accura thinking my velocity might jump up but with BH 209, ww209 primers, and a converted plug the 90 (v) grain charge balked at ignition. It fired, but not like it should have. I reloaded with my usual 50 cal, .45 XPB load and it fired exactly like it was supposed to. The only thing I could come up with was that the light bullet and off-sized sabot wasn’t able to either seal well or offer adequate resistance at ignition. BH really likes a solid tamp but if what’s on top doesn’t have the physical bulk to offer sufficient resistance I think problems can arise. It doesn’t imply that the powder is at fault but rather one of the little glitches that comes with BH. All powders in the black powder sub realm come with something that annoys someone especially when one considers that different guns and components other than the powder can have such a broad influence on how things work.