my Low dollar 318 hop-up project
Great thread thanks for posting.
Fyi to clean the valves what I did was put valve stem in a table top drill press and turned it on. Sprayed a little caeb cleaner on it. Then put a brass wire wheel in a hand held drill and cleaned with both drills on. Took a minute per valve.
The drill press keeps the valve turning so you never are in "one spot" too long and damage the valve.
Great thread!