I think Colt is making a good decision by doing that ( .456 throats). If that simple measure offers an additional safety measure, I am all for it. Colt never increased the cylinder size on the SAA when both the new service and even the colt cowboy used a bigger cylinder. With Colt stating the slightly bigger cylinder on the cowboy was for it to make deeper cylinder notches for the bolt to enter. On a SAA 45 colt chambered cylinder, it appears there is about zero room for error when cutting bolt notches.