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simonkenton
August 27, 2010, 05:56 PM
My brother has a 1917 Smith and Wesson.
You load the thing up, and it will fire fine, all 6 shots.

Load it up again, and the gun is jammed. The trigger won't pull, the cylinder won't turn.
You have to jiggle the cylinder a little to make the thing work again.

Then, it may fire the entire cylinder, or it may jam again on the second or third shot.

It doesn't matter if it is .45 acp or .45 auto rimmed ammo, it doesn't matter if you use full moon clips or not.

My brother took the gun to a gunsmith in Greer SC, the guy said he took the gun apart, could find nothing wrong, lubed it and put it back together. He pronounced the gun "fine."

Didn't affect it at all, it jammed just as bad after this "repair" as before.

Any suggestions?

hooligan1
August 27, 2010, 06:07 PM
I own this very same pistol, it actually is an old KC police issue, it has troubles also. They keep telling me it's a timing issue, as mine cannot be fired double-action anymore, I suspect it's wore out, but I cannot afford to have it fixed at this time. It can be shot single action, but I never shoot it. You might have to send it to Smith and Wesson.:)

BruceM
August 27, 2010, 06:39 PM
I doubt Smith & Wesson will work on anything made pre 1957 because parts are no longer available.

Bruce

mister2
August 27, 2010, 11:28 PM
Try asking the S&W forums:

www.smithandwessonforums.com

http://smith-wessonforum.com/

g.willikers
August 28, 2010, 03:27 PM
It might be the trigger return spring, also known as the rebound slide spring.
If the trigger doesn't always complete going fully back to the reset position, the gun can act like you are describing.

BillCA
August 28, 2010, 04:26 PM
Load it up again, and the gun is jammed. The trigger won't pull, the cylinder won't turn.
You have to jiggle the cylinder a little to make the thing work again.

Is this an original Model 1917 revolver? Or is it one of the new "Classic" versions of the 1917?

Does the trigger reset to the fully foward position?
If you use snap-caps, can you duplicate the problem?
When malfunctions occur, can you cock the gun single action without extra effort?

Look for burrs or peening in the following areas:
The cylinder stop notches (burrs or peening)
The cylinder stop
The recoil shield (burrs)
The center of the extractor star (burrs on the lugs)

With cylinder open, retract the cylinder release to the rear and slowly cock the gun until the hand rises in the window. Look for any burrs or hang ups there. Ensure the hand withdraws completely when trigger released.

Based on your statement of "wiggling the cylinder" it sounds like it may be the cylinder stop (bolt) or the cylinder hand hanging up for some reason. This could be due to burrs or peening of the cylinder notches or similar "fit" problems with the stop and one or more cylinder notches.

Operational checks:
Check that the cylinder stop in the bottom of the cylinder window moves freely. If not, add 1-drop of oil or Dexron ATF for lubrication.
With an unloaded gun, slowly pull the trigger and make sure the stop lowers every time.
As the trigger is pulled a bit further, ensure the stop "pops up" again well before the hammer falls.
With your off-hand thumb, put light drag on the cylinder during the trigger cycle. Ensure the stop engages the cylinder notch before the hammer falls. If it does not, the gun needs to be retimed. Repeat on each chamber.
Make sure the hand withdraws completely inside the frame window when the trigger is released.

http://i241.photobucket.com/albums/ff111/BillCA/Hobby/misc/Parts_chart_640.jpg
S&W J-Frame action - except for the mainspring, generally the same as your 1917


Other possibilities (none of these are good things).
- Cracked hammer pivot pin
- Cracked trigger pivot pin
- Fractured rebound slide spring stud
- Cracked pin on hammer mainspring stirrup.

If any of the pivot pins have cracked, they can be replaced by a gunsmith, IF you can find replacements. Otherwise one needs to be machined by hand. If these are fractured and are flexing during operation it can cause parts to jam instead of glide in the same plane.

The mainspring stirrup, located at the rear of the hammer is where the mainspring attaches. This can cause binding too.

10-96
August 28, 2010, 05:07 PM
One of our dispatchers had a M27 that had a badly bent ejection rod or crane. You could tell it was dragging on a portion of the cylinder face as it rotated past the bbl/forcing cone and when it got carboned up- it compounded to the point of not working at all. Study your cylinder gap for changes as you dry-fire 6 or 12 times.

Also, is the mainspring screw turned all the way in? If not, as a result of a goobered triggerjob, it can prevent followthrough of all parts. Never mind- it if was that- then it would happen just about all the time.

Unclenick
August 28, 2010, 05:27 PM
Good point on the gap. I have a used later model Smith that came with only a 0.002" barrel/cylinder gap. You could tell heat expanded it against the back of the barrel by the cylinder face scrape marks. So, I would just right off take an automotive feeler gauge, and with the cylinder closed, see what leaf fits in? 0.004" to 0.006" is what I usually hope to see. If it is less than that range, it may be the cause.

James K
August 28, 2010, 09:43 PM
Another possible problem is the ejector rod unscrewing and binding on the front housing. Make sure the rod is tight before shooting; if it comes loose, some blue Loctite on the threads should prevent the problem.

(P.S. BillCA's picture is excellent, but is of a modern S&W, which operates the same basic way but has little resemblance to an original Model 1917.)

Jim

10-96
August 29, 2010, 04:47 AM
On the ejector rod threads... somebody help me out here- Were the early one's left or right hand threads? He might need to know that before he twists on it very much.

Also, some of the older models had/have a pin free-floating inside the rebound spring. Anybody know what it's for, why it's there, and who's idea it was? I always leave them in there, but I've never found one to malfunction because it wan't there.

Oh, and before you go twisting on the ejector rod (once we establish which direction to turn it) insert two empty shell casings into the cylinder holes about halfway to keep from breaking the alignment pins. AND don't use pare toothed pliars- if you don't have the proper tool, pad the plier jaws with a bit of thin leather. That'll prevent getting "goober job" marks on your rod.

Eagle0711
August 29, 2010, 10:27 PM
A lot of good ideas so far. Try a thoruogh cleaning and oil.

triggerman770
August 30, 2010, 10:59 AM
I have one in the shop now with the same problem. S&W calls the part inside the frame that attaches to the cylinder release latch "the bolt" this part is not moving far enopugh to the rear, and the hammer makes contact and halts the whole process.It is also known as the hammer stop bar.It has a plunger and spring in the rear that pushes it forward. If the spring pushe it too far forward it locks uo the gun. The cylinder centerpin protrudes thru the opening in the frame to make contact with the nose of the bolt. If the spring for the centerpin is weak or missing it will allow the bolt to come too far forward, which is probably the case in your situation. with thew side plate off and the cylinder closed look at the bolt/hammer area to see if the bolt is out far enough to block the hammer. If so I would replace the centerpin spring and the bolt spring. These may be available at Numerich or Jack First.

pilroler
September 6, 2010, 08:55 AM
10-96
According to Kuhnhausen, the pin inside the rebound spring on N frames is a trigger stop

10-96
September 6, 2010, 12:59 PM
trigger stop
Well that's just ingenious... in it's own simple fix kinda way. Thanks!

James K
September 6, 2010, 01:26 PM
I think triggerman may be right. If the center pin is not pushing the bolt back far enough, the gun can't be cocked. That is a safety precaution to keep the gun from firing unless the cylinder is fully in place. It is my understanding that the feature has been eliminated on the new Bodyguard due to the different method of locking the cylinder.

As to the trigger stop, the earlier type used a small plate, set into a slot in the frame and kept at a specific setting with a small screw. It worked, but was complex, so S&W went to just using a pin inside the rebound spring. It is seldom quite right from the factory, but can be made just as good as the old one with some cut and try. (Cheap - use nails; cut and file until you get it right.)

Jim