I asked this on the gunsmith forum but no luck. I have a 1975 27-2 in great condition. Here is the thing. Sometimes I can cock the hammer as slowly as possible and all is well. A few minutes later when I try it the hammer cocks before lockup. Sometimes I can cock it fairly quickly and it will not lockup before cocking. No specific chamber. Spent cartridges in all chambers. The gun shoots great with no spitting. Clean as a whistle. It has done this for months and through 10 range sessions. Anybody experience this before? It’s driving me crazy.
Thanks
Dewy

Carry up problems are very common among older revolvers. More than likely due to wear and tear on the hand/ratchet interface, or perhaps it was not fit properly when it was initially assembled at the factory. If you have a qualified, trusted gunsmith in your area, a slightly wider (.001" - .002") hand will likely solve the issue.

You might check it for end shake on the cylinder (or yoke) also. An out of spec headspace can contribute to carry up being late. Rear gauge or headspace should be .010" - .014", measured between the rear of the cylinder and the breechface. (after a thorough cleaning and wipe down)

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Ret. LE, FA Instr, S&W Armorer

HOld the hammer back and pull the trigger on a chamber that has not locked up. Sometimes this will bring the chamber into alignment.

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Charlie

The very first thing I always check is end shake. If you have very much it can cause slow lock up. Cylinder is able to slide farther away from the recoil shield AND the hand. Hand doesn't engage and move the ratchet as much. Plus, it is a simple fix. Always check and fix the simple stuff first. Marking the chambers is also a good idea. Might seem random, but, if the chambers are numbered its easier to id a problem child. Dots of white out, small stick on numbers anything

No end shake at all. When it starts having trouble, it is slow on all chambers. When it’s good it’s good on all. That is weird to me.

Gun wasn't meant to be cocked as slowly as possible. Often able to make DA revolvers malfunction doing this. Just use the gun normally.

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No life story has happy end.

Does it function properly in double action?

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Pine_Worker
Ex-LEO, NRA Life

it not uncommon if cocking very slowly,i`ve had it too

Not uncommon when done slowly. Give the gun a deep clean and try it again and also in Double Action. If it still does it in both modes, then worry.

I tried this on both of my 4" 28-2's (They were in very close by) and both did this if I cocked them really slowly. Slower than I would ever normally cock them, so it's not a problem.

I understand completely. I like my guns to time early, carry up in Smith terms. I know that in firm single or double action shooting that they will work fine, but I am not satisfied with that. I like to feel a Smith cylinder stop engage and the hand slide by the ratchet. Your solution is to install a slightly wider hand, sometimes .001 larger and sometimes .002. This assumes all other tolerances are in spec. Since you asked the question, I will assume that you are not familiar with the insides of the gun, so I suggest an armorer or gunsmith that works on Smiths for the work. The part you need is less than $20.

It is not an oddity, it is really quite common, especially as guns wear. There was a period in the early 1970s when a lot of guns were mistimed from the factory.

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Richard Gillespie
FBINA 102

Brisk movement will move the cylinder into battery.


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My fault that I didn’t make my question clear. It is the inconsistency that I don’t understand. Sometimes it locks up when cocking slowly. Sometimes it doesn’t lock up when cocking swiftly. At times it works perfectly. In double action it seems simultaneous. It is the only one out of 14 revolvers that I own that does this. Any thoughts?

I would suspect the the extra variable in the testing scenario is the position/direction of your finger or thumb on the trigger or hammer when testing. There is enough gauge between the hammer and trigger components, which include the hand, that depending on the pressure used, and slight angle differences, you can get different results every time.
I've noticed that some of my revolvers don't carry up as well if I fire them or dry fire them double action with my off hand.

This anomaly it would seem, is more likely to occur with revolvers that are right on the fence as far as carry up is concerned, like your model 27.

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Ret. LE, FA Instr, S&W Armorer

Just to eliminate another possibility, you might try a toothbrush under the extractor and clean that space under it on the cylinder. Couldn't hurt..