Cylinder Stops....

[DougCarden]

I changed out my cylinder stops on my 625 and my stock 627. I was noticing a little slop on the 627 and thought I would just do both at the same time.

627 (mim) it was .003 smaller than the new one (mim)

625 (steel) it was .0018 smaller than the new one (mim)

I still had a bit of slop on the 625 so I looked at the frame and noticed that there were some rough edges on the top of stop on in the frame. I lightly peened them back down and then lightly filed the top, making it smooth again. That did as much as I am going to do without a oversize stop, which I dont think I need right now. This gun started life as a pingun and had over 20k through it of hard pin loads before I got it, and I have put over 25K through it as well. I think it is ready for another 25 or so....

I think it is fairly obvious to say that the steel part held up much better than the mim on in the 627, which only has at most 20k of light steel and ICORE loads along with about 8K of pin loads.......

The cylinder stop wear is more pronounced on the 625 than the 627, obviously due to the steel stop vs. the Mim part on the 627 and more rounds down range. The ole lead babbit made them all smooth again though

I just made an observation today with this and wanted to post the info. I think you can guess my thoughts on mim parts in my beloved Smiths.....

Regards,

DougC

[bountyhunter]

I changed out my cylinder stops on my 625 and my stock 627. I was noticing a little slop on the 627 and thought I would just do both at the same time.

627 (mim) it was .003 smaller than the new one (mim)

625 (steel) it was .0018 smaller than the new one (mim)

I still had a bit of slop on the 625 so I looked at the frame and noticed that there were some rough edges on the top of stop on in the frame. I lightly peened them back down and then lightly filed the top, making it smooth again. That did as much as I am going to do without a oversize stop, which I dont think I need right now. This gun started life as a pingun and had over 20k through it of hard pin loads before I got it, and I have put over 25K through it as well. I think it is ready for another 25 or so....

I think it is fairly obvious to say that the steel part held up much better than the mim on in the 627, which only has at most 20k of light steel and ICORE loads along with about 8K of pin loads.......

Regards,

DougC

The slop you saw is primarily due to the stop peening the edge of the frame slot where the stop pops out of, due to rotational inertia of the cylinder. The stop also peens the edge of the cylinder notch it locks into. I wish they made the stops out of softer steel, since they are much easier to swap out than it is to have to "peen down" the cylinder and frame edges.

I agree the MIM parts seem to be sifter than the old ones. The rebound slides used to be so hard you could polish on them for an hour and never take off a thousandth. I started polishing an MIM slide on #600 sandpaper and in half a minute I was cutting away metal.