Dragoon with loose arbor.

[Moptop]

Hey folks, I recently picked up a CVA (ASM) 3rd model Dragoon off of gunbroker. This one was a new old stock with the original box. Nice fit and finish. I had the chance to fire it yesterday and it shot great. Upon reasembly after cleaning I found that the cylinder arbor is now loose and wiggles a little in the frame. I know it wasn't like this before I shot it. Is there a way to tighten it back up? Did I do domething wrong here? I know (think) I didn't overload it with 40grns of FFFg. I also found that the barrel wedge now bottoms out against the wedge screw. It does hold it tight but I thought that it should go in that far. Should I and can I get a wider, thicker wedge to correct that or is it necessary?

I'm asking all these dumb questions because this is the first open top Colt style revolver I've ever owned so I lacking in the experience department here. I've had nothing but '58 Reminigtons till now. I've read that quality with old ASM's was kind hit and miss so I kinda figured it was a roll of the dice when I bid on this one.

Any guidence is much appreciated as always.

 

[Doak]

Hey Moptop ~
My first guess would be that the heat treat, if there was one, is poor. The whole frame/arbor assembly should have been case-hardened as a unit.

Look at the back of the arbor where it ends in the frame, under the hammer. Is there a pin driven into the outer edge of the arbor? If so, ya can't rotate the arbor to tighten it. Wouldn't want to anyway, 'cuz it would misalign the arbor wedge slot w/the barrel slot. That's why the pin is in place, to keep the arbor from rotating.

The arbor & frame are not meant to be disassembled. It's possible to do, but ya gotta drill out the pin first, after annealing the frame. Things get complicated & aggravating real fast!

The treatment for this problem is to re-case-harden the unit. Quenching will shrink the unit slightly and tighten it up, & being properly heat treated, won't work loose again. At least not for a long time.

Other solutions, like Crazy glue, flowing solder around the arbor where it enters the frame, are temporary at best.

For the wedge, both front & rear faces of the wedge, when it's in the slot, & the front of the slot in the arbor, should be hard enuff to resist compression peening from repeated shots.

So far as I know, the barrel is not heat treated. So the back of the slot in the barrel can peen. The treatment for this has always been to dimple the back of the slot w/a punch, pushing some steel forward at the back edge of the slot.

Kindest Regards,
Doak

 

[rcflint]

I have drilled out the locking pin, removed and cleaned and dried the threads and used Locktite to reassemble. When that sets up, with the barrel in place to align everything, I tap the former lockpin hole for an allen set screw, which makes it easier if it ever has to be disassembled again.

 

[Doak]

It's too bad they don't put a set screw in at the factory! Especially since loose arbors are a known issue.

Nice fix rcflint. Would love to see your setup for drilling the pin. :-D

Doak

 

[J-Bar]

When the arbors on a couple of mine got VERY loose, I had a real gunsmith re-stake them, $25 per gun. If they only wiggle a tad, I would shoot them.

 

[Moptop]

Thanks folks for the info. I like the idea of tapping the pin hole and using a set screw. That makes sense. It is a shame that it doesnt' have a set screw instead of a pin but then it wouldn't be period correct. One question I have on that is when you tap it out do you also want to tap into the end of the arbor? I'm guessing that's what locks the two together?

I read one thread that suggested using a punch to set the pin in a little farther. I did that and it did fix the problem for now. I know this is only a temperary fix and it will have to be fixed correctly sometime in the future. It was also suggested that I not use the loading lever since it puts extra pressure on the arbor. I'll have to see what I've got in the junk box I can use to build a loading stand. Maybe I can come up with something that is dual purpose so I can use it with my Remingtons too.

 

[72coupe]

Don't do what I did in 1968. The arbor got loose on my 2nd model Dragoon and I made an oversize wedge. This broke the end off my arbor without firing a shot.

 

[Moptop]

72coupe, well that thought did cross my mind. Thanks for the info. I'm finding out that these open top machines are different colored horses for sure.