I have a model 66 which will not ignite on a regular basis (1 out of every 15-20 will fail)I have tried every possible reload and factory ammo combo. It is clean and the strain screw is all the way in. I can take rounds with light strikes out of my 66 and they fire in any other revolver 28/27/19/686 etc.

Any suggestions? Thanks.

Frame or hammer mounted firing pin? If frame mounted it could be a too short firing pin.

If the gun was not bought new the prior owner could have replaced the main spring with a aftermarket one and/or shortened the strain screw. I suggest that you replace both and see how it does.

Hammer mounted/used gun. I will try the spring. Thanks.

quote:

Originally posted by gsrider:
Hammer mounted/used gun. I will try the spring. Thanks.

If you want to fix it free you can slightly bend the mainspring. The spring was probably bent to lighten the trigger pull which is why you have light strikes. It doesn't hurt the spring to bend it.

quote:

Originally posted by gsrider:
Hammer mounted/used gun. I will try the spring. Thanks.

I just ran across one with the same problem. Careful measurement showed this one to be a shortened strain screw. Common problem, easy fix.
(they are 8-32)

I replaced both the spring and the screw; did not fix the issue. Ouch! I hate owning a gun that is not 100%. Thanks for the help.

Have you measured the firing pin protrusion from the breechface? Should be 0.055-0.060 or so inches.

Second question: what's the cylinder endplay?

Third question: have you checked the free travel of the hammer. With an empty weapon, pull the trigger to the rear and hold it. Now, with your thumb, move the hammer through it's travel. Any hesitation? Drag?

I would say WR is right, the only other thing is that someone loved oil and the guts is full of crud. If you know how to remove the side plate I would check it out. Does the hammer have shinny lines on the side of it. Could also need a bearing in it. Something easy I bet. Later - John