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salvadore
May 19, 2010, 09:27 AM
1917 and it works pretty good. The springy thing that fit in the sideplate, I think was a hammer block is gone. My problem is the double action pull after a cylinder or two tends to bind or drag or something. It does this only when loaded, the DA pull works pretty good empty. Any suggestions would be appreciated.

Scorch
May 19, 2010, 11:23 AM
Is it a Colt M1917 or a S&W M1917? The "springy thing" is called a cylinder latch spring, and it holds the cylinder closed. If the hammer block is missing, it needs to be replaced. Try Numrich for parts.

salvadore
May 19, 2010, 02:25 PM
Sorry scorch, I didn't mean so obtuse with that brazilian navy title. It's a Brazilian Navy surplus S&W 1917 that were on the market some years back. The springy thing wasn't a cylinder latch spring, I believe it was a hammer block and I have already searched unsuccessfully for another. anyway about that DA binding, dragging, ets.......

James K
May 19, 2010, 06:34 PM
The Brazilian Navy S&W was a Model 1917. Some claim they were new made, but I have one, and have seen others, with U.S. inspection markings.

In any case, the thing inside the sideplate is a hammer block, the second type S&W used. The sloped surface on the hand contacted a right angle "lug" on the hammer block, pushing it out of the way as the hand came up. It worked OK except that it was its own spring and could easily break (as yours apparently did) or become dirty or gummed up an fail to function.

(It was that type of hammer block on the Victory model that failed and led to the adoption of the current hammer block system.)

AFAIK there is no source for those hammer blocks; Gun Parts Corp used to have some, but they are all gone. (P/N N53 in their catalog diagram.)

Now to the binding. The fact that it binds only when loaded suggests insufficient head space. First, give the chambers a good cleaning with a wire brush. Then, try different ammunition. (Try without the moon clips!)

If those things don't help, it could mean chamber(s) not cut deeply enough, or a replacement cylinder not properly fitted, or some other problems.

I would suggest trying to find a gunsmith who is familiar with revolvers (not easy) because trying to DIY could result in creating more problems than would be solved. Cylinder and Slide (www.cylinder-slide.com) could do the job but they have a long waiting period and are expensive. I don't think S&W will work on those guns any more, as they have no parts, either.

Jim

salvadore
May 19, 2010, 09:36 PM
I've shot it without clips, and keep the cylinder pretty clean. It starts to bind after shooting a couple of cylinders. I doubt it has a newer cylinder since it looked as trashed as the rest of the gun. If it was a headspace problem wouldn't I see either deeply dented or pearced primers or lightly struck? I don't think I could ship it to a GS since it cost $95 when I got it. Anyway thanks for the info and advice.

DG45
June 19, 2010, 09:17 AM
Sorry to be getting to this thread so late but didn't notice it until today.

I had what sounds like a very similar problem with my old 1937 Brazilian contract version of the S&W Model 1917 Army 45. That cylinder binding problem is what started me searching for help and is what led me to the Firing LIne Forum for the first time.

I got some great advice which you could probably still pull up by using the search feature and see if you wanted to.

It turned out that the seating of my S&W's ejector rod was integral to the operation of the cylinder. Who knew? The solution in my case was to open the cylinder, unscrew the ejector rod (making sure to not lose the spring in the process) applying blue locktite to the threads, screwing the rod back in to the exact point where everything worked just right, then tightening the ejector rod down right there and letting the locktite do its thing. Never had a cylinder binding problem since.

James K
June 20, 2010, 08:21 PM
Cylinder binding after firing a dozen rounds or so can also be due to an insufficent barrel-cylinder gap; the cylinder heats up and expands forward, closing the gap and resulting in binding.

Another possibility is ammo that is out of spec or reloads that are stretched or have protruding primers.

I can't diagnose the exact problem without seeing the gun, but the other folks have also given some things to look for.

Jim

salvadore
June 20, 2010, 08:57 PM
Another possibility is ammo that is out of spec or reloads that are stretched or have protruding primers.

Jim, out of spec?..OK I'll buy the cylinder gap..I think its close.003...I'm thinking dirty something, cylinder gap may be it.

James K
June 21, 2010, 09:34 PM
FWIW, I consider .006-.007" to be about the ideal b/c gap. Over .009" I consider too much (though S&W doesn't) and under .004" I consider too little. Ordinarily dirt in the b/c gap is not a problem as it just blows out, but heat expansion of the cylinder will definitely bind things up.

Jim