One of the ideas behind using a Python barrel on a S&W frame to create a "Smython"/"Smolt" was to have the Colt rifling -- which was said to be more accurate with 148gr lead hollow-base wadcutter rounds -- paired with the S&W lockwork. This was apparently pretty popular with the PPC crowd, which made extensive use of the revolver and 148gr HBWC round, and it helped to wring every bit of accuracy out of a gun as was possible.