17-4

[toz]

I opened up my 17-4 and removed the hammer blocking bar, mainspring, hammer, rebound slide, trigger & hand, and cylinder. I lightly stoned the sear face to slightly alter the angle and reduce the trigger pull. I reassembled the parts. With the sideplate off I repeatedly tested the action and everything functioned perfectly. A trigger pull gauge indicated the single action pull had been reduced from 4lbs. to 3lbs. I replaced the sideplate and tested again. Double action functioning is as it should be. In single action, however, when the hammer falls the trigger immediately springs back into its pre-cock position and cannot be held back. This happens repeatedly. When I take the sideplate off the action functions perfectly. When I replace the sideplate the problem returns.

All the parts seem to be seated appropriately. When, with the sideplate off, I press down on different components with the eraser end of a pencil to simulate possible pressure points that might be caused by the sideplate the action still functions perfectly.

So, what am I missing here?

Thanks in advance - Bill

 

[500 Magnum Nut]

Is the strain screw pressure the same? Did you alter the strain screw?

 

[toz]

strain screw

I had returned the strain screw to the same setting it had before disassembly.

In further testing I found that the problem would begin when the sideplate was almost closed. I also could see, by looking up into the frame, that the rebound slide was moving to the rear as it should.

Anyway, after taking it apart and reassembling it for the umpteenth time I got it to work. When installing the trigger I heard a little 'click' as the trigger seated into position. The movement was 1/64" or less, just the slightest little 'click'. That did it. Whatever binding was taking place ceased. I'd really like to understand what was happening, but I'll settle for a functioning revolver.