Originally Posted by Hondo44

I've seen the rear elevation screw on all frame sizes, including post war Transitional 22/32 I frame Kit Guns. The I frame pre war target sight with the post 1932 improvement of the regular 2 elevation screws like K&N frames has been observed but is extremely rare, and may or may not be factory.

The only 'book' reference I've seen to the elevation lock screw behind the sight blade is in the 3rd ed., Page 159 bottom left hand corner under the 44 HE 2nd Model Variations heading indicating Pre-1931 examples may be found with a Two-screw adjustable rear sight….and some after 1931 may be found with a Third screw at the rear of the sight blade.

I know some are of the opinion that the 3rd rear screw is "not factory". However Roy's comments support the case that it is. One gun he commented on, a post war Transitional I frame Kit gun:


Photo credit: PALADIN85020

One could make the case that this rear sight screw is factory but only as a "rework" factory method on guns the owners complained about not holding elevation sight adjustments.

This could be one of those things we may never know for sure.