hello, I need to replace the cylinder stop on a pre model 10, it's a 4 screw (no screw at very top of side plate). ebay has all kinds but they don't specify if it fits a 3 screw or a 4 screw. can a 3 screw cylinder stop with the attached spring replace a 4 screw cylinder stop? Thanks!
4 screw cylinder stop problem
- Thread starter chris66
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A four screw cylinder stop is smooth in the area where the spring connects to it from the trigger guard screw and plunger. The three screw is drilled for the spring to insert in the cylinder stop and the other end of the spring inserts into its seat inside the frame. So, no, they are not compatible unless you find a way to fill in the hole in the three screw cylinder stop. As it has been over 60 years since the four screws went away, I'd say they are difficult to find. Is there a way to salvage the one you have?
Post a picture of what you have. I may have an extra I can send you, gratis.
The original K frame came out in 1899 and it was a 4 screw revolver because it did not have a cylinder stop screw in front of the trigger guard. A new cylinder stop complete with the 5th screw was introduced around 1905.
The post WWII S&W dropped a different screw, the top bug screw in the sideplate, in the 1950s making a different style 4 screw. The confusion is that we do not know which era you are referring to. Serial number is needed to determining which you have.
The post WWII S&W dropped a different screw, the top bug screw in the sideplate, in the 1950s making a different style 4 screw. The confusion is that we do not know which era you are referring to. Serial number is needed to determining which you have.
So your gun is the second generation of 4 screw S&Ws. The 3 screw guns appeared in the late 1950s and I believe the cylinder stop was redesigned then in order to remove the cylinder stop screw. If so, the stops would not be the same. Have you checked gunpartscorp.com? They sell parts by model or name and should have a section on post WWII guns, pre-model designation. Not an easy site to navigate, but take your time to find the right model.
I am sure that all cylinder stops from 1905 to the end of the 4 screw guns will fit. That means Victory and pre-WWII M&P stops will work fine. Be aware that you many run into different width stops, so fitting may be required. The reason is that the stop window would wear over time and replacements would often be made thicker to fill the slot.
I am sure that all cylinder stops from 1905 to the end of the 4 screw guns will fit. That means Victory and pre-WWII M&P stops will work fine. Be aware that you many run into different width stops, so fitting may be required. The reason is that the stop window would wear over time and replacements would often be made thicker to fill the slot.
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Hi Nightowl, I thought the problem was the hand not fitting the ratchets properly as the action would bind up half the time. that wasn't the problem so I tried the cylinder stop. replaced the m&p cylinder stop with my pre 17's cylinder stop and the action functioned perfectly on the m&p. I stoned the sides of the original m&p stop that comes through the slot and put that back in the m&p and it helped a little. worked fine without the main spring. binds really bad with the main spring on. I don't know what else to do to it.
It sounds like the lip of the cylinder stop is too short and is not coming down far enough to release the cylinder stop notch as the hand begins to rotate the cylinder. So either the nose of the trigger has been stoned too short or the cylinder stop point has been stoned too short, or both. Sometimes a new trigger will fix it, but the cheapest solution is to try a new cylinder stop.
I believe somebody used a 3 screw cylinder stop in a older 4 screw gun by filling the hole in the 3 screw stop with a short piece of round stock. If you figured out which size drill just slipped in the hole in the 3 screw stop and then cut it to length and used red Loctite to hold it in place it should work. Even if the Loctite failed the spring wouldn't let the filler piece come out.
that's a good idea!
PM me your address. I believe I have a few you can try.
