My older 366 will sometimes grab (especially when going fast) and roll the dropped primer to the right, jamming it under the shell plate. The primer pocket hole is evidently worn in excess to the right, enabling this.
Shell plate is as tight as it can be. Have not polished and waxed the...
I was doing some searching for a replacement return spring for my Pacific DL-155 after mine failed violently. After one miss, I found the product below works great:
GRAINGER APPROVED Ext Spring,Utility,6 OAL,37/64 OD,PK3 - 1NAF8|1NAF8 - Grainger