Chamber and grove size?

[will52100]

Been thinking about getting a "real" colt.  What's the word on the newer colts?  I remember reading somewhere that some of the 45's had oversize chambers in the .455 realm and a .451 grove size?  Has this been corrected?  The reason I remember was an article about a smith taking 357 cylinders and boring them to .452 to correct this.

Thanks