Interesting method of cleaning. The problem I see is the rifling or parts of it may become caked with fouling that can't be undone without solvents. This would make for an interesting test though. A comparison of a dry cleaned barrel vs. a traditional method of cleaning with solvents or oil...
We're slightly off topic, but I thought it worth mentioning. The CBC 62 grain stuff is apparently steel free as you have said. It's about the only 62 grain that is steel free that I could find. Plus it's pretty cheap in price. I bought 150 rounds of it but have not tried it out yet. Also...
This is the "best" option that I have come across for inch pounds/wide adjustment range/accuracy. I use it for my LMT MRP and scope mounting.
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