As for patch lube, a lot of us use mink oil for TOW, cheap and reliable. For patching I have found that #40 100% cotton pocket drill cloth from Joann's works the best for me. Much tighter weave than pillow ticking, the thickness is around .018 which is perfect for my .54 deer rifles and a .530 ball.
If you go with a Kibler, the woods runner in .54 is lighter weight with a perfect balance point, I have shouldered a bunch of them at the local long rifle show. I have lusted for one of these rifles ever since they came out, the problem is I have three .54s, two flint and one percussion as well as another percussion in .50, I just can't justify another deer caliber rifle.
My last build had a similar 38" barrel in .54, I love this profile and its weight and balance, I have made this gun my #1 deer hunting rifle.
For cleaning, I just discovered this stuff, 3 wet patches and 3 dry patches and you are done except for lubing the barrel. I am still in the testing phase on this stuff but so far it looks really good.
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