Quote:
Originally Posted by DuggerWebster
My question is about having it restored case coloring.. It looks similar to the DH models but not as much engraving. Did it even have case coloring..
Not sure if this would add to or detract from value and who does that type of thing any more.
Final question.. why case coloring? was it just for looks or some type of protection...
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The process is called Case Hardening. It is a heat treatment which imparts a hard shell (the case ) The word 'color' is not a part of any technical description of the process, and has been added by the gun trade, since the 'color' is what most think is the only part of the process. It's simply a secondary result. The reason is to harden the surface, to a shallow depth of 1-3mm, to give the product wear resistance, yet leaving the low carbon core it's ductility. There are many methods of accomplishing this, such as nitriding, and salt brine quenching, as done in the cyanide hardening process. Traditional case hardening was done by tightly packing the product in a high carbon containing mixture, generally ground coal, coarse ground animal bone, leather, and other organic materials. Heated to between 1350-1625F, held very briefly, where the grain structure of the product becomes open and refined, and allows the transfer of carbon to it's surface, and a few mm below it. It is then liquid quenched to capture that carbon transferred to it. Any holding at the critical temp, longer than necessary, has the negative effect of hardening the internal material, lowering the ductility. The colors seen on the final surface are random, based on the coarseness of the carbonaceous packing material. We've all grown to love the resultant colors, forgetting the process was performed for the hidden toughness achieved. That hardness is still there, years later, after the colors begin to wear off. Re-heat treating it is done simply to recreate the colors, and only reestablishes the hardness that was already there.
Your gun appears to be a P grade (grade 1). Yes, it was case hardened too.