just got in one JM stainless steel flat mainspring housing , one charles daly stainless steel grip safety and one CD stainless steel flat MS housing.
the JM mainspring housing looked perfect like the other one when assembled the plunger stuck about half way down in the mainspring housing!
after about two hours of cussing, hammering, oiling, heating, hammering more cussing-- i ended up opening it MS housing up with a drill.
once i got the plunger spring and that little pointy thingy out of the mainspring housing i measured it against ones that i know work. and the JM mainspring housing was not drilled out to the proper size and caused it to stick! a very HARD stick at that!
i went ahead and drilled it out to the correct size and it appears fine now.
the charles daly parts fit perfect like last time. so they are 100% so far.
the JM parts two MS housings and one stainless steel commander hammer have had TWO defects.
the JM hammer had an undersized hammer pin hole and today's MS housing was either not drilled at all or drilled with the wrong sized bit.
so out of three parts i have got ONE that was correctly made-- a ratio of 2 out of 4 !
the JTM safety works perfectly but had numerous sharp edges and a pointy end that keeps gouging my plunger tube all these little things are an easy fix with a rotary tool and a sand-paper roll.
the colt, S&W, and charles daly parts have all been 100% some did require a little bit of fitting nothing PITA like this last JM mainspring housing!
maybe others have had better luck with JM parts--but right now i think i will look elsewhere--