This may belong in Smithing, but I thought it may get more coverage here.

Has anyone ever "monkeyed around" with the center-pin and/or bolt spring? I have two j-frame Air Lites and those aluminum frames take a beating from the rod end during lock-up. I was considering replacing the center-pin spring to lighten the loading on the rod, but am unsure if any reduction in spring-force would affect lock-up. I guess the question would be....do I also need to consider lightening the bolt spring as well to insure positive seating of the cylinder once it is closed?

A little lighter engagement would also be better on the tiny-fingered wife that sometimes struggles with the thumb-piece.

I would think any spring lighting would result in unlocking during recoil, especially with a lightweight gun.

You are onto the very question I am driving at. To zero-in....I should have mentioned the weapon in question is the model 317, but the same would apply to any j-frame AirLite, but in this case....recoil is not much of an issue. These 317's have serious spring tension on the center-pin.My thoughts were that if I lighten both the center-pin and the bolt spring....things may equal out.

But you're still lightening the forces that keep the gun closed. The bolt spring is very light to begin with.

I hear you guys, but I just have this idea that forces of recoil from the 22 will not create the inertia we may be thinking about from a center fire caliber. Just a "little" is all I may try. The springs are not that expensive....like less than a dollar. I could order a handful to justify the postage and just give it a try. Maybe clip a coil off and see where it takes me.

I don't see the need for the same strength spring in the 317 as is in the....say 642 for instance and the center-pin is wearing a pretty good "trail" through the frame, which is thinner than a dime in that area. Maybe shaving/polishing the end of the center-pin would accomplish the same thing.

Call me nuts....I have been called a lot worse, but if you had a 317....you would know what I mean. That contact area is likely the weakest part of the gun and NOBODY wants to grind-down a pre-lock frame with the center-pin to the point it has to be sent home for warranty. You may get a new frame, but I bet it would not be a pre-lock frame.

I have a new 317 I just bought a few weeks ago. After reading your post I tool a look at the drag mark and it is pretty substantial. I also have a 442 and a 642 and the drag marks on them aren't nearly as bad. In fact, the circa 1994 442 almost has no drag mark at all. The amount of push required seems to be the same on all 3. Hmmm, food for thought!!!!!

__________________
NRA Benefactor

GOOD to hear from you Tyrod....not because you have a problem, but now I know I am not alone over this concern. The parts manual I have tells me the 640 and the 440 "family" use the very same spring as the 317. The pin may wear the back-strap to a certain point and then stop....don't know and may not know until some 317 long-time owner chimes in with an opinion. Both mine are pre-locks but little fired in each case, so I have not shot them enough to know how deep that grove may get cut.....and I don't care to find out. I do plan to experiment with a softer center-pin spring, or a slightly shorter pin that will engage the frame deeper in the pocket, yet still lock the cylinder.

I realize the gun would still lock-up even if it cut a grove all way through the pocket on the outer edge....the pocket does get thicker as the cylinder closes closer to home and I don't think it would ever wear to the point that it would not. I just don't want a notch cut through that area on the outer edge.

I will let you know what I do. If you don't hear from me....you will know I blew myself up.

My concern is whether my 317 got the proper heat treating or an inferior alloy compared to the centerfire conterparts. My guess is that the groove, as it were, will somewhat work harden over many cycles of opening and closing.

__________________
NRA Benefactor

Haven't gotten much interest here in this thread, which is fine. If any 317 owners stumble across this and have a concern, PM me and I will tell you what I did to (what I think) greatly diminish the wear-and-tear on the recoil shield.

What if you eliminate the lockup at the front and install a ball lock on the crane? That should lighten the load a bit. This is the route I had to take when I had a 2" barrel installed on my steel frame Model 625. I shoot near .45 Super equivalent loads in this revolver and I don't have any problems with lockup. At least not yet.

Dave Sinko

More than one way to skin-a-cat. You did what you had to do and it works....that's great.

I really do not think I will have any problems at all with the reduced power center-pin spring I installed. I sought some advice from Smith and they said....it's normal wear. I got a rep answer and was seeking an engineering answer as to why they thought it was necessary to install the same spring in a 22 as they do all the other j-frames. I won't a strong spring for a positive lock-up in my 357 magnum steel revolver, but I don't think the same spring rate is needed in a 22.