I just ran some ladders with Staball Match powder. It looks really promising. All groups were about 1/2 inch.
I shot the 75 grain 3GH bullets and Sierra 77 grain SMK.
Bullets were fired from a 20 inch custom build 223 wylde 1:8 barrel. The 3GH bullets grouped slightly better than the SMK and speed was also a little better. SDs were 4.4 3GH and 4.7 for SMK. Best group was a .227 from the 3GH and. 375 from the SMK. Best speed was 3GH 2714, SMK 2658. Neither load was maxed out. I think I can get a higher node on both before seeing pressure signs. I shot these using IR night vision scope during daylight. I have coyotes in my food plot and I have to fix that problem before I do more testing.