im looking for a firing pin for a mossberg model 40 anyone know where to find one

Havlins is the place for old mossy parts.

If one from a 44US-A would work I might have one...

numrich gun parts lists the model 40 and 44 as the same but i dont know

havlin says to call about parts for the model 40 i will have to give them a call tomorrow

Wife is down w/ a migraine right now so I dare not go into the bedroom and open the safe (she's a redheaded puerto rican .... I have the bruises to prove it)

But when it is safe to access the safe again I'll try to remember to get it out and take a pic for ya w/ a ruler, etc in picture for reference.

Just did some more looking, looks like my 44 and your 40 don't use the same pin - a *very* early 44 would though.

Led me to a post on rimfirecentral (DEFINITELY the place for rimfire anything) https://www.rimfirecentral.com/forums/showthread.php?t=1186651

Which led me to the actual seller, (Jack First part #623-419) but they are OOS.  But they do have a pic of what you need, with a ruler, and if you are OK with any kind of CAD-like program you could probably get the actual dimensions since it is all straight lines, etc.

thanks for the help i found jack first number today and called them and got on the wait list they said that they should be making more sometime soon

Excellent!

When you get yours going, if it is anything like my 44 the trigger pull can be adjusted, and it can be loosened over time and eventually get too loose to actually cock and hold the hammer... Just a little thing to watch out for

If your 40 has the screw holes on the sides for the scope/S-100/130 sight Havlins has a repo of the proper scope mount, they work really well