Further deponent sayeth not, Your Honour.
I have a few rusty one myself. Generally, you can clean it out pretty well with Fine or finer steel wool, then finish with broken Crocus cloth (cuts way too fast when it is fresh). As long as things are smooth, the rifle should be okay to shoot.
Army standard was different, and you could get 30 days of Extra Duties for a rust-spot in a chamber, so the barrels were marked in order that the wrong guy didn`t get punished. As far as the guy is concerned who actually allowed it to get rusty in the first place, I think he is STILL running around the parade-square with a packful of sand and his SMLE at High Port!
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