My favorite load is for my .243. 42.5grs of IMR4895 behind a 58gr Hornady vmax. It's not the fastest load, but it is the most accurate I've seen. It will put shots through the same hole at 100 yards if I do my part and hold steady. It's a great load for prairie dog hunting. Really flat shooting and I've taken shots with it out to 300 yards so far.
As far as handguns go, the only powder I can get as of the last few years is bullseye. I've tried it in 9mm, .45gap, .45auto, and .40s&w and .357sig. I've stuck with it on the .45gap and .45auto exclusively. It also works decent in the 9mm as well. But my favorite handgun load would have to be (with limited resources) a .45G.A.P 185gr Hornady HAP bullet from midwayUSA, with 6.1gr of bullseye. It's extremely accurate and consistent, but shoots extremely dirty.
And yeah, it's an old thread, but I guess it's still a good one for someone to comment on it this far down the road?