If you are shooting semi-autos you can use a solution of a 50/50 mix of peroxide and white vinigar and soak the barrels in the solution.
CAUTION!!!! this mixture WILL DAMAGE/REMOVE THE BLUEING FROM FIREARMS
NRA Life Member, NRA Range Safety Officer, NRA Certified Pistol Instructor, IDPA Safety Officer, USPSA NROI Range Officer,
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