A fine day at the range

[Nuclearcricket]

Kurt, nice shooting and you are a much braver man than I am. I have lapped just one barrel and it was unchambered. I did it the old fashioned way with a cast lead lap. At the breach end I ended up taking out some of the rifling but the barrel came out nice and shiny. A lot better than it was before I started.
For what you were looking to accomplish perhaps a couple of the adjustable barrel lap heads that screw on to a rod might have been a good investment. As they wear, they have an adjustment screw that expands them so you get more use out of them. They are available from MSC and other tool suppliers I am sure.
Nice to see your hard work did pay off, looks like you have a winner on your hands now.
Sam