Spiders? what? no not the eight legged variety but rust spiders. I client bought in a Perazzi shotgun that I'm working on which highlighted a small issue with some Perazzi guns. Don't for a minute think that I'm bad mouthing the guns at all; from working on Perazzi's I find them to have a solid and sound mechanism that give very few issues, the components of the mechanism are suitable substantial and fit for purpose, and the movement contained in attractively finished actions, creating guns that look and handle well.
The only issue I find which causes a problem particularly in the coin finished polished examples is that of rust. Its often said that Perazzis are "soft" guns, which is to say the metalwork of the action is either nor hardened or not made very hard. The mottled blues of colour case hardening on older guns are really a chance side effect of the colour case hardening process; case hardening means you can manufacture actions from softer more easily workable steels, after milling, filing, polishing, engraving and finishing in this soft state gun actions are usually hardened and this can be achieved in several ways. The traditional method is to bake the metalwork at high temperatures in a carbon rich oxygen poor atmosphere, which was traditionally achieved by placing the component parts in crushed charcoal in an almost sealed crucible, at high temperatures the carbon becomes free and can migrate into the surface of the steel once quenched this gives the action a tough hard exterior layer, and a softer core which allows the action to give a little so it doesn't crack under the repeated stresses of firing.
More modern methods are used to achieve the safe effect, including but not limited to; induction hardening, and cyanide case hardening, usually a beneficial side effect of hardening is in increased resistance to rust. I'm not sure what if any hardening process is used on Perazzi actions but they are comparatively "soft". One issue with this is that the steel doesn't seem to have much resilience to rust. Some models have blued actions, which again adds a layer of rust protection to the metalwork, but the brightly polished "coin finished" actions seem to be effected rather badly. To combat this the bright Perazzi's are coated from the factory with some kind of very fine plastic coating, and by and large this gives adequate protection against rust. However on older examples this coating can wear off the high spots and sharp edges of the action whence rust can begin to form, once it does this rust can microscopically creep under the surface of the metalwork giving us rust - spiders.
My client presented his gun with just this issue, he wondered if the little lines over the gun was the action cracking; fortunately I was able to reassure him this was absolutely not the case. What can we do about it? unfortunately we cant do much to increase the rust resisting properties of the metal, though blueing could be an option. What we can do is chemically strip the old coating, polish the action and apply a new coating; in fairness the guns probably over ten years old, so its taken that long for the coating to wear and the spiders to form a modest amount of labour will restore the action to its former glory.
I will have to get a better way of getting photos onto this blog as its proving a bit of a pain, hopefully ill resolve that soon!
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