1992 fit chart
The holster fit chart with my 1992 DeSantis catalog is decidedly unhandy for working backwards. Besides numbers being used for different handguns with similar frame sizes and barrel lengths sometimes different numbers are used for the same handgun in different style holsters. (Follow that???)
In the 1992 chart, 43 indicates a 3 inch barrel S&W N-frame and 44 indicates a 4 inch barrel N-frame.
This series is straightforward enough with 46 being a 6 inch and 48 an 8 inch N-frame.
K-frames are 11, 12, 13, 14 and 16 (with overlap) and L-frames are thirties - also for Colt E/I frames.
J-frames are 01 and 02, unless they're an S1 or G1 - all 2 inch.
Not intuitive, but not nearly approaching Bucheimer complexity.