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Sidelock hammer screw.

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32 Cal
Mar 15, 2024
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I own three T/C .50 Renegades. On my first one I have replaced the hammer screw and lock plate twice. Which meant sending the lock plate to T/C to have the screw drilled out and replaced. I understand that T/C is no longer in business and that I will need a stronger screw than what the company installed. So any Idea what grade of screw I should get. I do not really want to have to drill out the broken off screw.
The first step to not having to replace these screws is don’t remove the hammer screw untill the hammer breaks. The lock plate screw need only be firmly tightened, and it should last a lifetime.
The first step to not having to replace these screws is don’t remove the hammer screw untill the hammer breaks. The lock plate screw need only be firmly tightened, and it should last a lifetime.
I do not take the hammer off. T/C just has cheap screws for the hammer. And Remington is no help.
If you don’t take the hammer off then why are you messing with the screw?
Because the end of the screw breaks off and the hammer then falls onto the ground. Which then means I have to send the whole lock to T/C. Which is no longer possible. So I want a better grade of screw. Can you understand that? Now read my first post on this subject.
Well I guess your right. Since it seems no one has read or understood my first entry. My frustration with people and their Reading skills. Since I do nothing to the screw except pull the hammer back and then fire it and it then the end of the screw breaks off. How is it so hard to understand. It is called vibrational stop. Develops cracks and then breaks. I will just go to a gun smith. No offence Hawken Hunter but that is why the screw breaks off. And that is from an experienced metallurgist. All I wanted to know is what grade of screw is it and what higher grade of screw should I get.
No offense taken by me. I think people understand the question but are trying to understand why the screw would break. I can understand the hammer taking shock and possibly breaking but I still have a hard time seeing how that screw would take any shock unless there was side force on the head. Good luck, hopefully you can figure it out. Does the hammer fit tightly on the tumbler shaft or is there slop there? You mention when the screw broke the hammer fell off. The hammer should be tight on the shaft. If it isn't maybe that could be causing your issue.
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The screws are probably made of 12L14. Hammer, and the other lock screws, are usually made of leaded screw stock. That steel is about one step stronger than cold peanut butter. That is because it is easy to machine and the strength required is very low. You will not find any "hammer screws" made of "better" steel such as 4140. I suggest making your own screws out of whatever you think will work better.

I have never has a single hammer screw break off in a tumbler is half a century. The screw has no stress on it whatsoever.

The hammer is supposed to be so tightly fitted to the tumbler that it takes a fitted square punch to drive it out. To install a tumbler on a hammer required some sort of press. There is a taper fit on the square section. The fit is extremely tight. As previously mentioned, if the hammer is loose on the tumbler, it is not fitted properly, or properly installed.

Tightening the screw is irrelevant to the fit of the two parts. IF a guy had a loose fit and tried to make the hammer tight on the tumbler with the screw I would expect the screw to break.

If a guy were to try to use the screw to seat the hammer on the tumbler using the screw, I'd expect the screw to break.

IF the tumbler to hammer fit was loose I would not be surprised if the screw broke after use and repeated tightenings.

The screw will never break if the hammer is correctly fitted and installed onto the tumbler.

Being a TC gun, realize that they were not perfect. I know some people think they were perfection. Sorry, they were not. They were built in mass and on a budget. Quality was not a high priority. Those guns were made of cast parts. They were not hand fitted or well finished. They were simply thrown together quickly. The main goal was to keep the price down and sell product. I would not be surprised if the hammer and tumbler were not fitted properly as originally made. Perhaps make a new tumbler that actually fits the hammer. That is what I'd do. Being a metallurgist that should be no problem.
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the problem arises when people use that wimpy screw to draw (attempt) the cock onto the axel.
don't ask how i know this.
i have several replacement screws but can't remember where i bought them.
It's that farmer tight that cracks the shank on the screw. they are not made to torque the cock.
i will look and see where i got the replacements, they seem to be of a better metal than the originals.