Been doin this 3 dacades plus. Is why im into fur trade. If you boil new or rusted traps, in muratic acid, like for cleaning basement pipes...it will clean rust off old, n new will rust as u watch it, min u pull em out. After that, agree with rest, logwood, walnut something that will etch into rust, n wax em if possible. If you ever browned a barrle ... same thing... acid 8dip n humidity... it will rust...finish is up to what u want it to be...
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