S&W 1937 Brazilian Contract, Phase #2

[Jkrem]

With all the parts now in hand, I headed to my workshop with the last two parts from Ebay. Both were new old stock 1917 parts, and are nice. I’ve finally figured out how to assemble and disassemble the gun, so after about 10 minutes I had the trigger and hammer groups in and things seemed to function fine. I dropped in the cylinder and put the side plate on, and said a prayer. The S&W gods were not smiling at me, as I now have a gun the works beautifully on one cylinder (#3, I marked all the positions) in both single and double action, and hit or miss with double action on the other 5 cylinders. None of the other 5 positions work single action. It appears that I have a timing issue. As the hand is one of the new parts, I’m guessing some of the notches on the ejector are worn or not being engaged properly by the hand. I’m going to try reassembling a few times with a bit of better lubricant and see if anything changes. If nothing else, I guess I can fire her single shot on the #3 position. I’m amazed by the quality of the machining of the parts in these pistols. More to come...

[Harter66]

Even in 1937 they were still hand fitted . So I would expect to have to adjust parts to fit .

For it's little value after strenuous search and research as far as parts go excluding cylinder and frame heat treatment N Frame parts are N Frame parts . A 1917 will take an M29 44 mag cylinder but obviously wouldn't be a good idea to shoot that way because the frame isn't up to it . I'd bet a smooth 44 mag cylinder in a M29 frame would take a steady diet of Ruger 45 Colts though . Carry on .

[Ajohns]

I went through this on a Colt Army double action. I know, they're different. Depending on the wear on your ratchet, I'm not sure that's the final answer. Maybe remark the good timed chamber at #1 and from there, see how things line up on the remaining chambers. Make sure things are tight, make sure everything is clean, make sure your bolt and such are not wore. And if the ratchet is wore bad, you maybe able to find a better one and see how its timed after that.

[Der Gebirgsjager]

Ratchets and hands are just about the trickiest chore in revolversmithing. Fortunately, although they're getting scarcer, the parts aren't all gone. It's just about impossible to diagnose your problem remotely, but start with the hand. Don't file the ratchets. Some of this is logic. We might make the assumption that the cylinder used to index properly and that the hand is at fault. This theory is kind of reinforced by the fact that 5 of the 6 cylinders behave the same. Much better to fit the hand to the ratchets than to alter the ratchets. You'll have to look and look at it and study it and see what it is failing to do. Is the hand engaging the ratchets, or is it too short; or maybe too long? Is the sear spring present? Is it deformed (easily replaced)? Is sufficient forward pressure exerted on the hand to make it engage? Do you have a copy of Kuhnhausen's S&W Shop Manuals?

DG

[Wayne Smith]

Definitely get Kuhnhausen's manual but also check out Jack First for parts.

[salvadore]

When you get your timing issue resolved, you should check throat size. Mine ran .454+. Probably not a biggy if you shoot jacketed.

[Oyeboten]

Post us a nice close up of the Ejector Star

Did you replace the Hand?

[Jkrem]

Here are a couple pictures. The extractor and cylinder serial numbers match. Note that the frame and barrel serial numbers are within 1,000 of each other, but are higher than the cylinder by around 7,000. The crane number and the number in the crane recess don’t match either. The hand was replaced with a new one, still in cosmoline.
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[StrawHat]

... The hand was replaced with a new one, still in cosmoline...

There you go! Brand new, unfitted part! I know where I would start.

Kevin

[Outpost75]

Even in 1937 they were still hand fitted . So I would expect to have to adjust parts to fit .

For it's little value after strenuous search and research as far as parts go excluding cylinder and frame heat treatment N Frame parts are N Frame parts . A 1917 will take an M29 44 mag cylinder but obviously wouldn't be a good idea to shoot that way because the frame isn't up to it . I'd bet a smooth 44 mag cylinder in a M29 frame would take a steady diet of Ruger 45 Colts though . Carry on .

I obtained in a trade an M1917 with badly pitted barrel and cylinder. I found online a new INA Brazilian manufacture replacement barrel and a Model 29 .44 Magnum cylinder and crane assy. I sent the gun and parts to John Taylor to fit, line-bore and chamber the .44 Magnum cylinder to .45 Colt, having cylinder throats .4525, leaving the cylinder full length, shortening the barrel extension where it protrudes into the frame window, cutting a new forcing cone and rebluing the gun. I now have an accurate, trim and functional .45 Colt S&W DA which I am very happy with, and which shoots to the sights with the same Accurate 45-264H and 7.5 grains of Bullseye I shoot in my 1920 Colt New Service. A "full charge" but safe, stout and effective field load.

Pics of my "Sewer Pipe" .45 "before" and "after." Thank you John!

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[Petrol & Powder]

Impossible to diagnose long distance but I agree with Strawhat that the hand is a good place to focus on. A new hand is probably too long (which a far better problem than too short). Before you start filing and polishing, take a good long time to look at what is happening.

Does the cylinder have end play? Will it cycle with empty casings in place? When it fails to lock up in DA is the cylinder bolt rising up?
Is the cylinder failing to carry up or is it being thrown past the point of lock up?
Take your time and evaluate why it is out of time. Not all timing issues are the same issue.

[Jkrem]

I have a new 1917 extractor coming from an armorer’s estate. I appreciate all the suggestions, and I will be spending some quality time with all the parts once the extractor arrives. My thought is to have enough quality parts to send to a revolver-smith. Have a great holiday weekend.

[JRD]

Be sure to do your function test and fitting with dummy rounds or empty brass in the charge holes. The cartridges themselves help take up play between the extractor and cylinder.
There are so many things to consider that all need to happen in the proper sequence for a DA revolver to work properly. Consider it a learning experience and enjoy the process of learning.