Dig--- Interesting. The Purdey finisher gave you info that doesn't quite jive with what I know about lead though. Here is a quote from a scientist---

"Paints used to contain lead because lead oxide is a white pigment with very good "hiding" properties. Paint contained lead years ago because lead oxide was one of the few pigments available. Lead, in the form of lead chromate, was, and still is, used in some specialty paints such as primers for steel bridges and ships because it has good anti-corrosion properties. It is also still used in yellow highway paints, because no substitute has been found that works
nearly as well. Today, lead is not used in paints for domestic uses."---Vince Calder

Hence, there would be no reason to put lead in a essentially clear (certainly not white) oil that is used to seal and /or protect wood. It would pigment it white.

However, he may know something I don't know. However, I would ask him what properties this lead was supposed to provide to the oils used on gunstocks?

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