I set down to load some Swift ammo last night and my cases wouldn't fit the shell holder. I have already loaded for this rifle once using Hornady brass and an RCBS #3 shell holder. Last night, I was using my New unfired Winchester brass and it won't fit. A trip to the LGS solved the problem with new shell holders but has me wondering why will the Hornady brass fit the #3 but the Winchester brass won't?? I know the simple answer, they are different sizes but why would Hornady change the rim size on the brass?