New Barrel For My Seneca


Apr 7, 2019
I’m putting a 45 caliber round ball barrel on my TC Seneca. It’s a spotless .36 caliber squirrel rifle and one of the best carrying little guns I’ve ever held. I’ve got a cut rifled 13/16” Green Mountain barrel blank and am fitting the breech plug right now. It’s rifled to 1:66” for round balls and is 36” in length, although I’m going to shorten it up to keep the rifles balance. Once I finish fitting the breech plug I’ll dovetail the barrel for the underlug and sights. When that’s finished I’ll use silver solder and install the under rib and thimbles for the ramrod, then rust blue it as the final touch. It will take a couple 2-3 weeks but should turn out very nicely. I almost went with a .40 caliber barrel but I’d rather have a 45 for deer. I’ll try to get some pictures of the rifle and my progress posted as it progresses.
Here’s a couple pictures of the barrel, under rib, thimbles, sights, and under lug. There’s not a lot of parts but there is a lot of fitting required with small files to make everything fit correctly. Since these photos I’ve dovetailed in the under lug. I have some work to do on the snail and tang hook for it to fit the stock and tang, along with the front sight and soldering the under rib And thimbles. The breech plug won’t have any of the scaring that’s there now when it’s finished, and I’m adding a brass accent ring between the breech plug and barrel. It’s slow but hopefully it’ll shoot well. It wouldn’t be my work if I didn’t add a little of my blood to it as well. While fitting the dovetail for the under lug the little 60 degree triangle file bit me. Now that that’s out of the way I can make some progress. Lol.
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Also if anyone is thinking of a small caliber muzzleloader build or barrel, I have two 13/16” TC breech plugs still on the barrels if anyone needs them. They are pretty hard to come by these days. The barrels aren’t usable but the under ribs and breech plugs can be reused. I don’t want anything for them, figured it may help someone looking for one.
Good progress Joe and generous offer for someone. Dan.
I’ll keep at it. I’m in no rush and it’s therapeutic tinker time for me. The 1137 steel of the barrel should take the rust bluing very nicely. At least is has on previous Green Mountain barrels I’ve did for a few friends. If it turns out like I see it in my mind it will be nice.

As far as the 13/16” breech plug and few other parts go. I have 2 extra and if I can help someone with one of them so be it. It’s frustrating to have a project in your head, and that’s where it has to stay because you can’t get a part. I’ll keep one as a spare but I don’t need them both.