M27-2 problem

[ncgin]

Just acquired a 3 1/2" M27-2, (p&r) sn# N37xxx and have run into a problem I've not experienced before. Lockup, crane fit, is tight.

I haven't fired it yet. Dry firing, the single action is fine, and double action is fine IF done at a slow, steady pace. A single hard DA pull will lock the trigger back, and the cylinder will be locked BETWEEN chambers (bolt jamming up between cylinder notches). Manually moving the cylinder will release the trigger, as will prying the trigger forward. Sometimes, pulling the hammer back and releasing it will free things up.

Timing problem? DA hammer fly problem? What's a quick fix? Anyone know if S&W still works on these older revolvers.

Thanks in advance.

Norm
Dallas, TX

 

[500 Magnum Nut]

I know what it's not and that's the cylinder stop.

I'm going to guess a sear problem. Using a feeler gauge,
check sear clearance to top of trigger while parts are at rest. S&W instructions allow .01 to .02 air gap. As you look at the parts the space will be wider on the right side closer to the trigger.

I know this picture is not that good but see where the sear and top of trigger get together, this space is where I'd like you to measure.

Also, make sure all the side plate screws are snugged up. Sometimes a loose side plate will cause the trigger and rebound to walk off position then bind.