I first loaded 30 Carbine many years ago for both an M1 Carbine and for a Ruger Blackhawk revolver. Back then the maximum load in the Winchester load guide was 14.0 grains of W296 with a 110 grain bullet. That load worked great but created a lot of flash from the revolver. The maximum H-110 load was 15.0 grains and it worked well also and was of course flashy like W296. So then I tried IMR-4227. When got vclose to the maximum load the cases would stick in the Blackhawk's cylinder. Even with 15.0 grains of H-110, the cases would just fall out of the Ruger and the velocity was higher than it was with IMR-4227. My favorite powder for the revolver was Accurate #9. It had little flash and gave good velocity. Years later Hodgdon sold surplus commercial ammunition powder that was called H-116. It was the same as old, discontinued W680 and the factory ammunition load used 16.0 grains of it. Accurate A1680 is a bit slower and I'm not sure I've seen any A1680 load data for 30 Carbine, and it may be too slow. The 15.0 grains of H-110 gave the highest velocities, even from the revolver. I backed off the load to 14.0 grains, which gave very good velocity and maybe extend the case life a bit. It was also easy to empty the Blackhawk cylinder with that load, but I preferred A#9 for the revolver due to the flash with W296 and H-110. I never did try H-4227 but sometimes I wish I had. I didn't really expect it to be much better than IMR-4227, but maybe it would have been. I tried 2400 and maybe HS-7. I knew when the pressure was getting up near max due to sticky cases in the Ruger. Full loads of W296 and H-110 never stuck. A max load of A#9 could get close though. A bit too close for my liking and I backed it off slightly. Velocity was disappointing with IMR-4227, even with the sticky case max load. Ramshot Enforcer is similar to A#9 but I've never tried it in 30 Carbine.
Despite some media reports, there were no AK-47s involved in the incident