M29-2 Cylinder Unlock

[Luke44]

Hi all. I have a late 70s 4" M29-2, pinned and recessed. I have not yet had problems with the infamous cylinder unlocking, but plan to start taking it as backup when pig hunting and want to be able to load it with heavier bullets for that 'just in case'. I am thinking to install an 'extra power' cylinder stop spring from Wolff Springs, and want to hear from those who have already done this to their 29s.

My question is, is it a drop-in replacement, or do you have to modify the cylinder bolt? I have read many threads where folks say installing the stronger spring fixed the problem, but only one person indicated removing material from the cylinder bolt might be necessary.

Thanks in advance for your replies!

 

[armorer951]

Sounds like you are worrying about a problem you don't have yet. Correct terminology for the S&W is cylinder stop.

If the cylinder is not staying closed during heavy recoil, you have a problem with a weak or broken center pin spring.

If the proper function of the cylinder stop is compromised by heavy recoil, a viable solution could be a stronger cylinder stop spring. As long as there are no other timing problems, or issues with the existing cylinder stop, the "extra-power" springs from Wolff should be a drop in replacement.

The malfunction you describe can also be caused by dirt and crud in the cylinder stop slots (clean thoroughly with a toothpick), dirt or excessive/improper lubricants on, around, or in the stop itself, damage to the slots themselves (peening), and improper fitting or wear on the ball of the cylinder stop. If any of these problems exist, the addition of a new and stronger spring may not fix the issue.

 

[muddocktor]

Welcome to the forums, Luke44.

I can't help you directly, as I've not installed an extra power bolt spring in any of my N frames, but I have been inside the internals quite a bit. And I have pulled the bolt, spring and plunger out of at least 1 of my N frames. And as long as the spring is basically the same diameter and length, I see no reason why you would need to modify anything. But, I just looked on the Wolff website and didn't see any replacement bolt springs for sale. I saw cylinder stop springs in both standard and extra power, but no bolt springs.

 

[Pisgah]

I had a 29-2 with the problem years ago. The extra-strength spring cured it and, yes, it was a drop-in. The spring is no larger, just constructed of a heavier-gauge wire.