Speaking of Armi San Marco...

Doc Hoy

New member
Mostly for Mykeal's interest.

Couple of days ago I was whining about a cylinder gap in an ASM 1860 Army. Perhaps y'all remember that I had just bought the pistol on GB. Pistol is in great shape accept for the cylinder gap which was at .018 with the wedge firmly set.

In that thread I was considering the action to close up the gap and I had resolved to knock a couple thousanths off the surface of the barrel where it meets the frame.

This I did with great success. I used a milling vice to hold the barrel. I made a couple of vice pads so as not to mark up the barrel. These pads were made from some 1/2 inch thick polyethylene plastic. I got this plastic from my last employer. It was a construction company and we used this plastic in four by twelve sheets to line the beds of dump trucks. I brought home about a dozen snubbles about two feet by four feet. I put a sheet on the top of the work bench I use for my pistols. It treats my pistols like velvet.

I took a little off of the locating pins with fast wheel and then beveled them with a file. The gap closed up to about .004 to .006. The wedge fits into the pistol a whole lot better now too.

Heeding Mykeal's advice to work judiciously lest the job get crooked and ruin the accuracy, in the first pass that touched metal, I think all I did was take off the bluing. Three passes is all it took to get the pistol right. (At least I hope it is right. I haven't shot it yet.) The mating of the barrel to the frame looks every bit as good as it did before I started, and as I said the cylinder gap is looking a lot better.
 
Sounds like it went very well. I'm not surprised at how little it took to get a big change in end gap, and I'm glad you took your time and great care. The proof will be in the shooting, but it sure looks like you saved the gun at this point.
 
You worked on the barrel assembly; I'm not aware of a name for the particular area of that assembly, so I'd just describe it by function: the barrel assembly lower fitting. Not very creative, but hey, you know what they say about age and cunning...
 
What is the name of the area of the barrel I worked on? "Heel"?

I and several others I know refer to it as the "barrel lug"

Closing the gap on the 1860 is an easy task as you work on the barrel lug and not the frame. Removing those locating pins can be a pita. Did you fit the arbor when you closed the gap? The arbor should bottom out in the arbor hole in the barrel lug one or two thousandth before the lug contacts the frame.
 
Yup!

MCB,

I had already determined that there was plenty of relief in the arbor to barrel connection. I put the barrel on the arbor angularly offset and then turned the barrel to check how much play I had in the arbor/barrel, I had at least a 16th inch overlap between barrel lug and frame.

Yes...I know about those pins. I have tried pulling them before and vowed I would never do it again.
 
Barrel lug is good for me.

There, now, see? I learned something. :D It was worth chewing through the restraints this morning. Took me almost an hour.
 
Hope you don't mind

Mykeal,

As you are painfully aware, it sometimes takes me a long time to come to the point in my posts. I hope y'all don't get to mad about this.
 
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