Trooper mkIII trigger not resetting

[silicosys4]

I took the Colt trooper mkIII .357 out today
While firing some moderate handloads the trigger failed to reset three out of five times in double action.
After firing the trigger stayed fully back until the hammer was pulled back 1mm or so then the trigger reset.
I loaded some empties and could not replicate the problem dry firing in DA.
Any ideas as to what the issue might be would be appreciated.

 

[ColtPythonElite]

Had it happen to a MKiii. Dried oil gumming action. Take off grips and soak overnight in Ed's Red.

 

[Jim K]

We are seeing a lot of reports of guns not functioning in the current cold snap, and that sounds like another one. Guns that fail outside work perfectly fine when brought indoors; guns that folks greased (on the advice of some experts) have failed when the temperature hits 20 degrees or below and the grease gets as hard as tar.

The answer is to winterize your gun, including places like firing pin tunnels, by removing grease and lubing with light oil and, if the gun will become cold, wear gloves so your hands don't stick to it. It is well known that powder burns faster and builds greater pressure in the heat; it is less well known that it burns slower in extreme cold and the result might be a gun that doesn't function.

Jim

 

[silicosys4]

Well, it was blue dot, but it wasn't that cold, about 45 degrees or so. We'll see what soaking does for it, I guess. I've had the sideplate off for cleaning on a few smiths, anything I should know if I have to take this one off?

It's a recent purchase, so I haven't shot it much, but I'm hoping nothing is broken. I've heard some parts are not easy to find for these.

 

[Walkalong]

Those actions are pretty tough. I bet a good cleaning/flushing out fixes it up.

 

[MikeJackmin]

You also might have a speck of grit that lodged itself in a bad spot for a while.

With the grips off, you can soak it pretty well, or hose it down with your favorite spray. I'd avoid disassembly if possible. Just use anything other than WD-40 and chances are it will be fine.

 

[gamestalker]

There should only be 63 very small springs and retainers that will come flying out when you remove the side plate. Na, just kidding!

Hope you get it working reliably.

GS

 

[Ash]

I've taken apart a Mk III and it isn't the easiest to get back together again.

 

[harvester]

It could be gunked up but it also could be a weak spring. It has a trigger return spring that must have one of its two legs on the shelf in order to have correct power to reset reliably. If you are able to take the side plate off you will see the trigger return spring and be able to tell if the leg is on a shelf or not. I do not have a pic handy but that would be the best visual.

 

[Walkalong]

The Trooper Mk III action is not only very strong, but quite simple compared to a Python or OMM.

 

[smkummer]

Colt MKIII action

I have fixed one or two of these that had all kinds of issues by simply taking off the stocks (grips) and spraying either some cleaner and/or lube into the action. You can also spray down the hammer area and in the frame where the hand comes through. The action was first advertised as "perma timing" by Colt and unless its been messed with, it really needs no service other than lube. Good luck

 

[Hardtarget]

One day my Colt just started a malfunction right in the middle of a string of six. My brother in law took the sideplate off. There was a sliver of lead in the works...tiny sliver. It was keeping the hammer from full cock. Tweezers and a steady hand and we were back in the "draw and shoot two" drills. I'm glad he found that little slice of lead.

Mark