Thanks guys. It's finished as good as I can get it. Plugged the nipple hole and filled it with Vinegar for a couple days and then scrubbed it out. Whatever rust I may have missed will have to get shot out.
I just did a refurbish on 2 rifles. Lapping is good but I went a step further. Took a dowel rod.
, 1, .5 for 50cal and 1, 7/16 for 45cal. Cut a groove at angle to match twist and same width of groove. Cut a bit for each from a file. Put a piece of leather in the dowel groove to act like spring tension. Ran the bit 100 plus strokes in all grooves. Polished with steel wool. Produced very nice defined deeper grooves an land edges. Both rifles shoot markedly better than before.
Here ya go.
One other thing. When you make the first few strokes go slow and make sure the dowel is turning. I found that once I was accustomed to it I could turn my hand with the twist. When it's all sure hold a marker inline with the bit and stroke to make spiral line on dowel. This will let you know if the bit jumped out of the groove. Really nothing you can do but pull it out but it helps to know that you get total number of strokes per groove. The bit I used cuts both directions. So if it jumped 2 times toanother same groove thats one stroke for that groove.
I also removed barrel and clamped on a table with cushion under it that way I could use the wall or cabinet to create a backstop so the dowel would stop right at the bit just protruding at the muzzle. Before I did that it was difficult not to pull the dowel all the way out then the bit would fall out and of course would go under anything just to piss me off. Made keeping up with which groove was in work too. Figured out putting tape around barrel and numbering the grooves helps a lot. But making abackstop was the best because you can really get after it when it's all working right, along with spiral mark. You may have to remark the spiral occasionally.
To get the bit angle I lightly oiled about 2 inches of the barrel then put a narrow piece of paper, about 1/4 barrel circumference, in the barrel then slid something that would lightly press the paper against the bore without moving the paper to get imprint. Important to keep paper centered inline with bore. Graphite the back of the paper. Put the paper on the dowel centered inline. Mark over rifling lines leaving transfer on dowel. I used a dremel but an exacto and a jewelers screw driver the right width and sharpened is easier to control to get snug fit groove. The bit doesn't have to be more than 1/2 inch long. Too long and it will be difficult for it to follow the groove. If there is roughness a few drops of oil will help. Once the roughness stops you shouldn't need oil.
I recommend doing 50 strokes per groove then clean. Then repeat. The build up of loose metal will start wearing on the dowel rod thus why you will need to remark the spiral.
Let me know how it goes.