Repairing Hammer Axles On Smith & Wesson Revolvers

Back in 1973, I bought my first Smith & Wesson .44 Magnum Model 29. At that time, these guns were much in demand, so I placed my name on awaiting list, sat back, and waited. After what seemed like forever, the call finally came, and I went along and paid my $203.50 for the gun—nickel-plated with a 6-1/2-inch barrel. Although I had wanted a blued gun, I took the first Model 29 that came along, and have never regretted purchasing the nickel-plated version.

Not, that is, until awhile back when the hammer-stud broke, and I was informed by Smith & Wesson they would have to strip the nickel plating to facilitate the repair. There was no way I was going to have that lovely old finish compromised by a repair job. I liked the way the gun looked, and appreciated all its little scratches and nicks—memories every one—and was not about to lose that "patina." So I let the repair go for what eventually amounted to several years.

The gun still fired, broken stud and all, and I didn’t use the gun much, so what the heck. If it ain’t broke too bad, don’t fix it. Recently, I pulled the gun out and did some shooting with it, and also took some measurements, discovering things I had never known about that revolver in all the 30-odd years I owned it.

I wrote about the size of the chamber outlets (and the barrel swap to 4 inches) in a recent issue of American Gunsmith, but the discrepancies were not really serious issues, in the grand scheme of things. The dimensions were wrong, but there was nothing I could do about it. But I sure as heck could fix that broken axle. The old hammer studs, or axles— whatever you wish to call them— were pressed into the left side of the frame.

They didn’t have much of a protrusion past the hammer on the right side, which gave very little support there. The right-side hole for the stud was, of course, in the cover plate. In fact, the studs had a very rounded and tapered point that probably didn’t get any support at all from the sideplate. The fillet where the axle portion met the larger-diameter head of the stud (pressed into the frame) was not very big.

Later versions of the gun have a much larger base radius on the hammer stud and a correspondingly larger relief in the side of the hammer. The tiny radius of the fillet on my old gun was essentially a stress riser, and I’m sure mine is not the only old Smith on which that stud has broken. To put things into perspective, I have documented the firing of 4,125 The gun still looks untouched, but it has a new axle within its original finish. The gun began life with a 6.5-inch barrel.

The grips are cut-down, factory-original wood.

A factory repair would have required replating, something the author didn’t want to do. Getting this hole in the right place was easy, because most of it was already there. rounds in that particular revolver. That’s not a lot by some standards, but most of my shooting was done with full-power, Elmer-Keith-type handloads. Eventually the axle broke. I actually have no idea when the stud broke, but the gun functioned nearly perfectly after the stud broke.

The broken part stayed in place, and by luck was actually still very slightly inserted into the frame on the left side. The only indication I had of any kind of problem was that the double-action pull was occasionally sticky, and my tests indicated that stickiness might not have been from the broken stud. (More on that problem at another time.) Of course, when I pulled the sideplate one day to clean the gun, the broken stud and hammer fell out.

As I said, I contacted S&Wand they would fix the problem, but wanted to strip the nickel. I’m sure they would have replaced the entire stud, base and all. It was their design, after all, and I’m sure they’d stick with it. As noted, the axle portion of the original stud was smaller than the head of the stud. The head had axial serrations to prevent turning, and the whole thing was pressed firmly into the frame, probably with the use of a dedicated press during manufacture.

But I didn’t need or want the entire stud to come out. The base of the part was securely affixed into the frame, and I chose to leave it there. What I planned to do was to make anew axle out of drill rod, and make a hole as deep as I dared in the remaining stud and even into the frame behind it, to accept my new axle.

Then, if I could, I’d give the new axle better support on the right side by letting the full diameter of the axle stick out past the right side of the hammer and on into the cover plate, assuming the hole in the cover plate was not too big. As it turned out, I had to enlarge the hole in the cover plate slightly, which ended up giving excellent support to that side of the new axle as well. But I’m getting a bit ahead of myself. First, I had to make the axle.

I had a suitable piece of drill rod large enough that I could turn it to proper size. Please excuse my lack of memory or expertise here as to materials; I don’t know if the drill rod was wateror oil-hardening. I’ve always used water to harden it, and that’s always worked for numerous firing pins I’ve made over the years. On the lathe, I turned the drill rod to a good fit within the hammer, so the hammer spun with no slop.

Clearly you want a superior finish on your last cut on this axle, so spin it fast and take your time (high speed and low feed). I made the new axle plenty long enough that I could trim it to length once I had it fitted in the hole I was about to drill in the frame. Drilling the hole was the next job. You might think it would be necessary to use a mill, or at least a drill press and lots of jigs and fixtures to get the hole perfectly centered and perfectly vertical. Here I got lucky.

The broken piece of axle had left a slightly rounded depression—you guessed it—dead center in the base of the old stud. If you are not that lucky, you may have to resort to cutting or filing off the surface of the broken stud to make it perfectly flat against the left side of the frame, then find the center by some clever means, center punch it, and then go to work drilling. I found a number-size drill that was a bit smaller than needed and carefully drilled the hole with a hand-held cordless drill.

Of course, you must make sure the drill bit is held square to the frame, and if you don’t have the skill or experience to do that reliably, by all means use whatever fixtures you may need, including the drill press. Then I opened the hole up with the appropriate number drill so my new axle would just slip into the hole. The only other trick was to make absolutely sure I didn’t drill through the side of the gun. I forgot to mention that I stripped all the lockwork out of the frame completely, including

This was done to make the new hole a bit tighter on the new axle, basically fixing a minor blunder. the latch mechanism. That let me clean up everything perfectly once the job was done. The other end of the axle support was essentially already begun. The hole in the cover plate formed an excellent guide for my final-dimension drill. Once again I made sure I didn’t go all the way through the plate.

I left quite a lot of stock on both sides, partly because I’m chicken but also because you don’t need that much to support the axle. Remember, the gun worked very well with just a loose piece of steel rattling around inside the hammer. Now I had support holes in both sides. Yes, I got the main hole too big, and staked the edge to give added support to the new axle. You can do better than that, I’m sure. Now came the big question: What should I use to secure the axle into the frame?

While I knew it would work with absolutely nothing in there, I wanted to keep the axle in place whenever I disassembled the gun, and not have parts fall out and become lost. Accordingly, I turned two tiny grooves on the part of the axle that would be held within the frame, so that the grooves would give added grip to the bonding agent. I was almost ready to install it. Next, I cut the axle to length. That was easy.

I put the axle into the frame and installed the hammer over The rounded, tapered end of the original pin got essentially no support on the right side, which made it easier for it to break. The author used a Dremel cutoff wheel to trim the new part. it. Then I marked the axle where I wanted the cut, about 1/8 inch (or a little more) past the hammer. Then I took it all apart and made the cut with a thin abrasive wheel in my Dremel tool.

A hack saw would work, especially if you can hold the new axle in a collet on your lathe. I don’t have collets, so I held the axle carefully in the vise and used the Dremel. Then I slightly rounded the outer end of the axle, the portion that was to enter the side plate. I stuck the axle dry into the frame, put the hammer over it to hold it roughly in place, and tried to fit the cover plate over the parts. I kept on slowly rounding the end of the axle and trying the fit until I could get the cover plate

This new system gives added support to the axle. The new axle worked perfectly, and preserved the external finish on this old revolver. to slip readily over the end of the new axle. The outer end of the axle was still well supported, despite the slight rounding I had just done, and it was easy to install or remove the cover plate. Then I gently polished the new axle so I could see what I was doing, and gave it a heat treatment.

I heated the axle red hot, quenched it in water, cleaned up the surface polish to be able to see the colors, then slowly reheated it until I got the desired straw color, and again I quenched it. This is how many parts of early Lugers were colored, including their triggers. I’ve used similar techniques for making firing pins in the past, and this system works for me. You may have a better system. I wanted a surface that would be hard enough that the axle would not wear out quickly, yet not be brittle.

Now it was time to secure the axle into the frame. I could have used any number of things. Solder might have worked, but I didn’t want to risk discoloring the outer nickel-plated surface. That left epoxy or something similar. Brownells Acraglas or Steel American Gunsmithing Association News Check out the center spread in this issue of American Gunsmith on AGI’s Complete Video Armorer’s Course.

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You may wonder about my sanity, but I once super glued a front sight onto a 1911, and shot the dickens out of it. It held perfectly until I bumped the front sight blade and sheared it off. I have used superglue on radio-controlled model aircraft, and know a little about its usefulness and limitations. You have to degrease the surfaces thoroughly, and then degrease them again. With intelligent preparation, superglue does a remarkably good job.

Suffice it to say, as of this writing, the axle is still secure and has not rotated in the frame. I would bet I’d have a devil of a time getting that new axle out if I had to remove it. After all, there isn’t any axial strain on the part. As I noted, it would have Gunsmithing Association Membership Services, Norwalk, CT 06856-5656. Or call Also available are three-ring binders that hold a year’s worth of American Gunsmith issues. Order several to house your collection safely and securely.

Binders are $8.95 each (shipping and handling FREE), available from American Gunsmithing Reader Services, Beachwood, OH 44122. Allow 4-6 weeks for delivery. worked with no glue whatsoever. Just be sure to clean up the joint so nothing binds the hammer when the glue sets. That’s about it. To date, I’ve put several hundred more rounds through the old Smith & Wesson, and the new axle works perfectly. This repair would work on blued guns as well.

The beauty is that there is no indication on the outside of the gun that anything has been done. The new axle gives better support to the hammer than the old one, and I’m convinced this repair will last forever. If I got the heat treatment wrong and the wearing surface doesn’t hold up, all I have to do is remove the old axle and stick in anew one. This system should work well for you, too, and could help preserve a beloved exterior finish that factory repairs would destroy. ■ AGA Corner

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