The Firing Line Forums - View Single Post - .223 Full Length Sizer constricts case mouth. Case won't accept bullet.

**Unclenick** · August 3, 2011, 11:52 AM

Expansion is needed with cast bullets to stop the brass shaving them hard, but a chamfer is adequate with jacketed bullets, even with square bases. Note that manufacturers don't expand case mouths loading new cases, and sometimes have a little shaved copper at the mouth of the case to prove it.

August 3, 2011, 11:52 AM	#42
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,057	Expansion is needed with cast bullets to stop the brass shaving them hard, but a chamfer is adequate with jacketed bullets, even with square bases. Note that manufacturers don't expand case mouths loading new cases, and sometimes have a little shaved copper at the mouth of the case to prove it. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle