Sixgun
The Millbastard
After reading another thread about "heavy for caliber trying a slower powder" I decided to try R22 with 147's in my 6547. HOLY MOLY!
Loaded at the lands, slightly compressed, in new cases. They absolutely would not stabilize. I did a ladder test and velocity was from 2350 to less than 2500. R22 probably isn't the best for temperature stability but they didn't get cold that quick (40 degrees) I was really surprised..I was expecting 2700-2750 max speed. I dont think fire formed cases would've been any different. In the end..I think Hornady 147's are just too heavy for the 6547...but maybe it's more about that long bearing surface. That being said I will try another powder.
Loaded at the lands, slightly compressed, in new cases. They absolutely would not stabilize. I did a ladder test and velocity was from 2350 to less than 2500. R22 probably isn't the best for temperature stability but they didn't get cold that quick (40 degrees) I was really surprised..I was expecting 2700-2750 max speed. I dont think fire formed cases would've been any different. In the end..I think Hornady 147's are just too heavy for the 6547...but maybe it's more about that long bearing surface. That being said I will try another powder.