220 Swift Chamber

[Jdaniel343]

I just got some cerrosafe and cast my 220 Swift chamber. (Winchester heavy varmit, H&S stock, piller bedded with bedding block).
In the past this rifle shot 0.50 MOA or better with tuned up brass and handloads.
All dimensions from the cast are approx. 0.002 under sammi chamber specs except for the neck dia.
The chamber cast measures 0.262, my fired brass measures 0.258 to 0.259. My reloaded case measures 0.253.
Is this ok?
Should I set the barrel back and rechamber?
Thanks

 

[Boyd Allen]

If your rifle shot well enough before, then it did so with that chamber. Yes, the chamber neck is larger than it should be. How many rounds does the barrel have on it? It would be nice is barrels just wore out at the end of the throat, but that has not been my experience. If you choose to rebarrel in the same caliber I would certainly take a long look at all case dimensions when ordering a reamer. My usual practice being to work from a sized case (sell used) to determine body dimensions.