SP101 cylinder latch problem

I've got a couple of the French Railway SP101s and I noticed on one of them I could spin the cylinder clockwise with very little effort with the hammer down. I picked up a new cylinder latch from Midway and installed it last night with minimal fuss. That appeared to fix the original problem but a new one popped up.

During function testing everything works like it should in DA. In SA function testing the action hangs up and won't cock 2-3 times per cylinder. If I let the hammer move forward a little and try again it will come back to full cock but I may have to do that 2-3 times before things work again. I haven't marked anything yet to determine if this happens randomly or on the same chamber each time.

I need to figure out if it is something I did during reassembly or if I need to do some fitting of the replacement part. I'm also fine sending it back to the Mothership if it's potentially something beyond a little bit of stoning and fitting. If I do that I'll put the original latch back in and toss the replacement in my spare parts.

Thanks!

This type of malfunction is probably one of the most difficult to troubleshoot. A gunsmith would want to have it in his hands to duplicate the problem so he feel what is happening and that might give him an idea where he wanted to start looking. As much as I hate to say it, I would take it apart again and look for any burrs or rough marks on the new cylinder latch. While trigger assembly is out, pull the trigger and see what the cylinder latch does or how it feels. While it's out, look at the opening in the frame for the latch and insure there are no burrs there that might be interfering with the latch. Pull the hammer and look at the hammer dog and the sear area for any abnormalities.

Thanks, that's sort of what I was afraid of. Considering it's a 1993 production, I will probably reinstall the original latch and see if I can get a call tag to send it to the factory for a spa day. I'll still check those things while I have it apart but I'm pretty sure this is one of those tolerance issues that prevent "drop in" parts from...dropping in.