S&W steel cylinder bolts in 329PD

J

JDinAZ

Inactive
S&W steel cylinder bolts in 329PD UPDATED.... Works Good

Anyone else had this happen. Broke the top 2.5 to 3 threads off my MIM bolt in the 329PD carry gun so I grabbed a steel one to replace it, going to have to rework the steel one a bit to make it function the way I want it to and to fit properly. It needs to let the cylinder roll open like butter the same as my 629-3 does or as close as possible to that smooth functioning.

I dug into the Smith Armorer's three ring binder to verify proper fitment. I knew it was not the exact correct part number when I ordered it but its steel not MIM so its well worth it to me to do the mod and run it in my gun since I do carry this one everyday out here in AZ full of 240g white box.

When I get done with it I'll update this with a picture or two.


Hope this helps some of the S&W revolver guys or anyone else for that matter.



Well its done and it works great. Well worth it in my book. Let me know if you want one.

This is the current production MIM bolt. Note the recess at the bottom of the pivot stud, this is a sure fire way to tell which type of bolt you are looking at.
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This is the Steel bolt and the current MIM bolt side by side before I modded the steel bolt
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This is the Steel bolt after I added steel and reworked the pivot stud
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Works good. Heres a Video. This part unlocks very smooth when you cycle it by hand and just nudge the cylinder open. My 329PD will never be smooth as a stainless gun the springs are too heavy and the cylinder is too light to just roll like butter.
https://youtu.be/o7obVSwPYk0
 
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You are correct, the MIM bolt is made of powdered steel and a binder agent. And a magnet will stick to it.

When I mentioned steel I am talking about the solid steel type bolts before the MIM parts came along

Just loaded a picture of my broken bolt
 
MIM starts out as a metal powder + polymer . This is injection molded , Metal injection Molded, This is heated to melt out the polymer. Then it is sintered [heated to higher temperature] to bond the metal powder.
There are a number of variables which will determine the final properties.
 
How does a cylinder bolt allow/prevent the cylinder from rolling "open like butter", unless it is too short. And what causes the threaded part of a bolt to just break off? Sounds like a sales pitch for another un-needed refinement made/sold by the poster's company.

Jim
 
James K said:
How does a cylinder bolt allow/prevent the cylinder from rolling "open like butter", unless it is too short. And what causes the threaded part of a bolt to just break off? Sounds like a sales pitch for another un-needed refinement made/sold by the poster's company.

Jim
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Agree.

As a S&W revolver armorer, I have no idea what "rolling open like butter" means when it comes to the proper fitting of the front of the bolt.

I like a normally smoothly opening and closing cylinder, myself, but there's more involved than just the bolt length.

Never saw a bolt have the threaded cylinder latch stud break off like that, either, but that doesn't mean it couldn't happen to a forged, cast or MIM part, under the wrong conditions, if it contained a defect caused during manufacture.

FWIW, I've known of more poorly cast parts than poorly made MIM parts. Some S&W MIM parts have seemed to be harder (without being brittle) than the hinges of the gates of hell, and the inherent exterior smoothness isn't a bad thing.
 
It was actually put here so folks know it can be done. Many will want to do this at home on their own which is why I explained the basics on how to do it. I never gave steel swap out parts much thought till I needed a new part in my gun. A lot of people don't like MIM parts. I'm one of the non-mim folks.

Yes the old steel bolts are short thus they have to have the pivot stud rebuilt. My MIM part in my 329 never did function as smooth as the one in my 629-3 so I was happy I figured this out and know some folks would want to do this themselves since it can be done at home by folks with some skills that enjoy doing things like this.

The threads broke off because I tightened it too much I'm sure but when they broke it was an eye opening thing for me never saw that before. So I asked it as "Anyone else have this happen" to see if it was a regular occurrence or just my gorilla tightening. Probably my gorilla tightening is the culprit.
 
"Yes the old steel bolts are short thus they have to have the pivot stud rebuilt."

I am not sure how many S&W revolvers I have handled but it has been at least one or two and I have rarely seen a revolver that wouldn't open easily due to a problem with the original factory bolt. (It is far more common to have problems at the front due to the extractor rod unscrewing, but that is another issue.) In other words, the allegation that the "problem" affects all "old steel bolts" seems to be made only to persuade folks to buy the poster's product.

A clever sales pitch, but still a "non-fix" for a "non-failure."

Jim
 
Yes the old steel bolts are short thus they have to have the pivot stud rebuilt
Click to expand...

The threads broke off because I tightened it too much
Click to expand...

AS the owner of 15+ revolvers with mim parts spanning 17 years of production I have never seen a broken one. If it did break I would send it back to S&W where it would be fixed under warranty.

Yes "Gorilla tightening " which is not needed could break it. I put a dab of blue locktite on the threaded Nut on the revolvers I own where the nut came loose repeatedly, rather than using extreme torque to tighten it.
 
True Jim .most of the newer style do function just fine, I never said they didn't. Mine did too for the most part but it had a little hitch in it but just a hitch wasn't enough go make me fiddle with changing anything. I carry that gun its not a shooter very often for me so it didn't bother me a whole lot. When I cranked down the thumb piece nut and the threads popped of which I'm sure was my fault I wanted something different to replace it.

Most of the older steel ones in old guns usually work fine since those had been fit when the gun was assembled at the factory. Mine had a little hitch but that was comparing a premim 629-3 to a mim 329PD two different animals. About like how some folks are fine with their triggers the way they come from the factory and some do a trigger job at home to tune it to their liking. I don't do trigger jobs on any of mine since I'm mostly a snap shot which is what I picked up as a kid in the woods in Ohio with a 22 getting squirrels. Is it the "right" way who knows but it works for me. Can and do I know proper form, stance, etc yes from when I was in the Marine Corps but the only time I really use it is when I break out the 50BMG.

I have never made an "allegation" about old steel bolts. Fact is that the old steel bolts have a pivot stud that is shorter than the newer ones. Grab a handful and hold them side by side. Atleast the ones I've had in my hands comparing are shorter. And they don't drop in and function well in MIM guns (old steel type bolts from numrich). But they do go in and will work they just catch cause the pivot stud is short.

They were never meant to go into the new style frames. So yes there is a problem that you have to correct if you want steel in there. If you just want a mim replacement then throw a new mim bolt in and call it a day. So if folks want to do this at home they needed to know what they need to do to make a steel bolt work in a MIM gun. Its a retrofit that I showed that most folks will do at home on the weekend

And by the way I get folks call me to ask about what to use to do these at home so I give that info away frequently at zero cost. I get the same calls for other things I do and I will always help them and talk them thru whatever they need even when. I get an email call or text at 8pm or on Sundays I answer and help.

For me its about making sure folks know what can be done. From what I can tell about a good many folks in this forum is they have been around these guns a good bit and many do this stuff on their own.

I even go as far as sharing the info from the Smith Armorer's binder I have to help folks out. My life isn't all about me making a buck which is the picture you are painting of me
 
Master Blaster said:
AS the owner of 15+ revolvers with mim parts spanning 17 years of production I have never seen a broken one. If it did break I would send it back to S&W where it would be fixed under warranty.

Yes "Gorilla tightening " which is not needed could break it. I put a dab of blue locktite on the threaded Nut on the revolvers I own where the nut came loose repeatedly, rather than using extreme torque to tighten it.
Click to expand...
Yes sir I learned the hard way on the over tightening. Now mine gets a little dab of loctite 222ms its the adjustable one for fine threads. Part of why I tightened this gun up as tight as I did was 25.2 oz launching 240g full house 44 mag and was worried about things coming loose
 
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