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Very nice...… your project takes me back to the first frontstuffer I ever had, ca.1967.
I made a caplock pistol, using the cutoff 8" section of a .444 Marlin barrel and a huge (8"x 12"x 2-1/2") walnut.
I fashioned a breechplug, threading the rear of the barrel for a short section from the head of a large stovebolt that I had welded a 3" long piece of one side of a hunk of angle iron for shaping into a tang.
The lock came from the junkbox of an older gunsmith I was acquainted with ($5), and I adapted a long tang SxS shotgun triggerguard ($3) to use on the pistol.
Those were the days...……….

Funny story on how I got the walnut, back when I was thinking about doing the project:
One day, while working "on the road", I happened by a woodshop housed in an old brick building - and so stopped to see if they had anything good available.
Just inside the door was a huge pile of thick (the size is above) wooden blocks with a walnut veneer on both sides of a walnut core !

The woodshop owner told me that the pile came about after he told a young apprentice to cut up a large old veneered desk, not realizing that the desk actually had a walnut core.

He only realized it when the odor of smoking walnut drifted back to his office, but by the time he got to the apprentice, it was too late.

He said I could have as many blocks as I wanted for $1 each.

I bought only 4
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