I would wash the cylinder, heat it with a hair dryer and apply cold bluing till it’s the right depth in color. You could polish it with 2000 grit paper first. I apply cold bluing with 0000 steelwool. Sometimes doing it with a q tip doesn’t work

E-gun parts has barrels?

I had a shady *** dealer sell me a h&r 22 revolver with one lug in the cylinder that looked to be chewed on. The locking slot was big. It shaved lead. I actually moved metal closing up the loose slot in the direction it had to go, to where a range rod worked and polished and reblued the cylinder shes acshooter now.
There is nothing a flat blunt piece of metal and a small hammer can do I saved it. You can’t tell I rolled the metal. Sometimes we have limitations sometimes we don’t. I tried to get a replacement cylinder from egun parts they sent me the wrong one.

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Plant garlic in the fall