Parts interchange

After using the Search feature and not finding my answer, I turn to you for your help. Are all the internals of a Medium Frame, i.e. OM 357, interchangeable with all the parts of an OM Large Frame and vice-a-vice. I need to have built one more .45 on a Medium Frame. Thanks for your help!

The only difference is the hammers, large frame is about 1/8 taller.
If you have the tall hammer the top can be adjusted or hit me up I have a extra medium frame hammer.

FWIW; the medium frame hammer works just fine on a large frame, it's just a tad short, a common found occurrence in OM guns.

A sharp eye catches it.


Hawkeye, Super, LG Blackhawk, MED Blackhawk, Single Six, Super Single Six, Bearcat.
Quality Old Model Hammer Photo Courtesy,,, weaselmeatgravy

Appreciate the help G2 and Weaslemeatgravy Was thinking they would interchange. Looks like just removing a small amount from the top of the large frame hammer would work.

the pawl is also a different length