Ancient Golden Age Precarved Kit Project

[Knobs]

Almost 40 years ago ( perhaps 1986) I bought a golden Age Arms Kit gun with a 42" .40 Green Mountain straight sided barrel and small Siler lock.

I abandoned the job after making a mistake but kept the kit. I picked it up recently and and am stumbling through it again. I don't have a bench or a vice yet so it's all being done in my lap.

I found this forum and decided to post progess to get feedback. Here goes. I'm not claiming that this is going to turn out to be a work of art.

I fitted the breech plug back in the day. Recently i dropped a .1mm shim washer, followed by a second shim to test my fit. It appears I'm a little over half a thou from making contact with the face of the thread shoulder. Rather than finding someone to turn a 5 thou off the barrel and re-fitting I decided to call it good. If I want to get anal I'll stone down a thicker shim washer some day and put it in there.

Decades ago, in my enthusiasm, I took a spoke shave to the precarved stock. It shows up as the lighter area on the first of the pics below. During the process of inletting the breech plug I realized I never should have done that. That's when I gave up.

About a month I go i got the idea to re-bend the tang. You can see the results in the two following pics. Not pretty, but functional.

Last week I finished the breech plug inlet and decided to work on the lock.

I used an RO sander to get the side panel flat and square with the top flat of the barrel. That's when the fun began.

in locating the touch hole liner I found that it's OD is just a couple thou smaller than the flat of the 13/16 barrel. That dictated a center drill on. the barrel flat. Next I located the touch hole center on the side panel and began messing with the lock position. Two problems popped up.

1.) The web on top of the ramrod hole wasn't thick enough to cover the OD of an 8-32 sideplate screw. I figured I could find a work around for that.

2.) If I did get the front side plate screw just under the bottom barrel flat that dictated a rotation of the lock plate that was going to either put the lock plate off the bottom of the side panel or cover up the touch hole and require skipping the touch hole liner and drilling a standard touch hole high in the barrel flat, angling it down to the powder chamber.

I decided to rotate the lock to place the sideplate screw UNDER the ramrod channel bringing the lockplate back onto the side panel as you can see in the pic below. We'll see how this works out. My concern is it's going to look goofy when done, especially on the side plate side, but I hope i can find some way to "hide" that.

I've inletted the bolster down to the point of full side panel contact by the lock plate. Surprisingly the inlet holds the bolster tightly with no movement. The lockplate outline can be seen in the picture below.

Now it's time to inlet the lock fully. The I'll get to find out if I laid it out properly and the pan aligns with the planned location of the touch hole. Man, the layout is TIGHT!

Knobs

 

[Sam squanch]

I’ve seen a few original guns with the lock not quite level, some were very nice guns when new.

 

[Tumbledown]

Looking ok from here.

 

[Eric Krewson]

Too late now, you have already inleted your tang, all of us have to file down the breech end of the barrel if the plug is a little too short. No big deal, just take a swipe or two with your file, check the plug seal and timing and repeat if necessary. It doesn't have to be pretty because the only thing that shows is where the tang contacts the barrel. If you are bottomed out and have a small gap, a little peening with a ball peen hammer will move enough metal to close the gap, a little draw to filing get rid of any hammer marks and you are good to go.

 

[stubshaft]

I built an Ohio Vincent half-stock with parts from Golden Age. Gotta have been over 40 years ago too.

Your build is looking good Knobs!

 

[ChuckJonesWagon]

If it’s not to late you could use a #6-32 lockbolt instead of a #8. I’ve done this before with good results.

If the lockplate is drilled for 8-32, you could silver solder the hole up, redrill and tap. I’ve done that before and the results were excellent.

 

[Knobs]

Too late now, you have already inleted your tang, all of us have to file down the breech end of the barrel if the plug is a little too short. No big deal, just take a swipe or two with your file, check the plug seal and repeat if necessary. It doesn't have to be pretty because the only thing that shows is where the tang contacts the barrel. If you are bottomed out and have a small gap, a little peening with a ball peen hammer will move enough metal to close the gap, a little draw to filing get rid of any hammer marks and you are good to go.

I appreciate the tip. I figured I'd need a full rev off the barrel to bring the tang back in alignment. Judging from where I am I'm about one barrel flat too far if I file the barrel breech down. I'd be fine if the sight dovetails weren't already cut.

At 18 tpi the other 7 flats to complete a full rev are around 50 thou. I was scared to attempt to file that much off and keep it straight.

On a more arcane note, I contacted Green Mountain about min thread engagement. They advised that if the installed the breech plug a minimum thread engagement of .55" would be used. That's 10 threads. I've got 8. I boogered up the bottom two treads due to the bottoming tap not seating far enough during the fabrication process.

I bought another breech plug and a 5/8 x 18 bottoming tap. The (McMaster Carr). Guess what? the bottoming tap is just a little too big for the female threads! So much for that idea.

Net-Net, if I turned one thread engagement off the barrel breech, and one off the breech plug front I'd be at. 60% of the GM recommendation.

I called a local Gunsmith who is supposed to have BP experience. His solution was to forget about it and use blue loctite.

I'm going with the spacer shim and loctite. It can wait until I make sure I don't mess this rifle up somewhere else!

Thanks Again

Knobs

 

[Knobs]

If it’s not to late you could use a #6-32 lockbolt instead of a #8. I’ve done this before with good results.

If the lockplate is drilled for 8-32, you could silver solder the hole up, redrill and tap. I’ve done that before and the results were excellent.

Thanks. I hadn't thought of that. I may go that route.

Knobs