I have a Brittish police issue model S & W although it is a .357 magnum, the barrel is stamped 38 special. It seems that people taking the mod. 66, 626, as well as other .357's are using .357 magnum ammo at the range, when in fact S & W said .38 special ammo should be used during practice, and .357 used for carry. The heavy, continuous loads of .357 magnum ammo has a tendency to crack the forcing cone, at the bottom of the barrel, this problem has been documented since the late 1970's.
Reason for the L-frame.