I recently acquired a 4”, 4-screw, pre-Model 18, K-22 with a broken rear sight blade . It is of approximately 1957 vintage, (K314xxx).

I have several questions that I need help answering, please.

1. For what height rear blade should I be looking? Where can I get it?

2. The rear sight blade screw has the early, flat slot-face. Where can I get that?

3. Are the screw threads of the same size/pitch (interchangeable) on both the early, flat slot-face screw and the modern rounded slot-face screw the same so I can use either one for my replacement rear blade if I’m forced to?? Also, are the sight screw nuts interchangeable?

Thanks for any help I can get. I hope I’m just not stuck with a cool paper weight!

Reach out to member (club gun fan). He has a supply of some NOS rear sight blades but not sure about screws. Certainly worth a PM or email. If you can get yours out, exact measurements will help him locate a correct replacement. If that fails you may wish to try Numrich.

__________________
James Redfield
LM #497

Another option might be member Toolguy.
IIRC he sold me one a year or so ago.