RE PRIMERS FOR THE 454, I HAVE SOME OLDER WINCHESTER FACTORY 454 AMMO WITH A 300 gr BULLET THAT IS A DEAD RINGER FOR THE FA 300 gr BULLET. WITH THAT AMMO, IN A 10 INCH FA MODEL 83, THE PRIMER WILL FLOW ENUFF AROUND THE FIRING PIN TO LOCK THE CYLINDER UP. I STARTED SWABBING THE CHAMBERS, AND CLEANING THE BRASS, WITH LIGHTER FLUID, TO MINIMIZE SETBACK AND THAT HAS SOLVED THE PROBLEM. BTW, A GREAT DEER ROUND. I FIGURE IT IS THE WW PRIMER THAT IS PROBABLY NOT AS HARD AS THE REM 7 1/2. FA RECOMMENDED THE REM 7 1/2 BECAUSE IT WAS HARDER, NOT HOTTER. I WAS GETTING PIERCED PRIMERS IN A 1st GEN COLT SAA 32-20 WITH PISTOL PRIMERS SO I TRIED REM 7 1/2's AND NO MORE PIERCED PRIMERS.