Nitre blue and hot blue are 2 different processes. Double barrels that are soft soldered together must be rust blued. If a set of soft soldered barrels are hot caustic blued, the residue left behind attacks the tin in the solder and destroys the joint. This can take years to happen, but it will. Never ever hot caustic blue a set of soft soldered tubes, the residue is almost impossible to remove short of removing and relaying the ribs.
Steve

Firearms imports, consignments


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