Interchangeability of revolver parts

[Wilson Custom Guns]

Hi,
I wonder if you can interchange MIM parts with the old machined parts on S&W revolvers?
Any advice?

 

[tomcatt51]

It's usually ok. I have a couple high round count 17s and 617s, old style "real steel" with the external firing pin crosspin, with MIM triggers, rebound slides, cylinder stop and the forged hammer (there's no compatable MIM hammer) with no problems except the usual sear fitting. The MIM triggers would sometimes have engagement issues with the "real steel" cylinder stop which was fixed by installing an MIM cylinder stop.

 

[Wilson Custom Guns]

Thanks for the info Tomcatt,
So they never made Forged hammers with the frame mounted firing pin on K L or N?
If I understand correctly, the frame geometry is the same, and frame pins are the same, so the parts would all interchange (excepting the firing pin issue)?

 

[tomcatt51]

Thanks for the info Tomcatt,
So they never made Forged hammers with the frame mounted firing pin on K L or N?

No forged hammer for the "MIM" K/L FMFP gun that I'm aware of. The "MIM" FMFP K and L frames use the same hammer. There is (or was) a PC forged N frame FMFP hammer for the "MIM" guns.

Yes the geometry / pin locations etc are the same

 

[Drail]

Even though the studs and pin holes are all within spec the parts may or may not be. Some times a part will actually drop in and function but you really can't count on it. Wear (or lack of wear) on mating parts may require some degree of fitting. I have seen plenty of guns where someone dropped in a part and the action barely functioned they way it was designed. There really are very few drop in parts in most quality firearms.

 

[tomcatt51]

I have seen plenty of guns where someone dropped in a part and the action barely functioned they way it was designed. There really are very few drop in parts in most quality firearms.

Somewhat true of the "good old hand fitted guns" where parts were actually "select fit". On an MIM S&W the parts are consistently "drop ins", the one exception being the sear, they (consistently) need the "bottom front corner" (short cut) trimmed slightly and the ratchets are still cut in place.

 

[Drail]

Give me them "good old hand fitted guns" every time.

 

[tomcatt51]

Give me them "good old hand fitted guns" every time.

Fine by me. I currently have 2 of the "good old hand fitted guns". A near new 3" HB 10-8 where I did the hand fitting it never got at the factory and a 629-2 I bought new that first went to a repair center, then went to the factory where the frame and other parts were replaced. Yep, "good old hand fitted guns". The 629-2, as delivered, woudn't hit an 8 1/2" x 11" target at 25' even with the sight at the limit of it's adjustment, "good old hand fitted guns".