I started a project recently with my H&R .223. The goal was to develop a subsonic load with 55 gr. GCs. I had to start somewhere, so I picked 5 grains of Bullseye and used small rifle primers to light it.
Airborne101 sent me some boolits sized to .224 and gas checked, but unlubed. I lubed them with two light coats of alox thinned with 10% mineral spirits.
I set up a target at 50 ft. with a 1" square bullet paster as the bull. I was really surprised that I hit the sweet spot on the first guess. I shouldn't have any problem at all killin' a 'coon with this load.