I think it was how they cured it but one of the gentlemen above would know for sure.
They were having trouble getting a sufficient supply of cured wood, so they developed a shortcut curing process involving the use of salt. Little did they know that guns made with the salt cured wood would cause all the guns to rust away where they contacted their wood stocks. There was a huge recall, and they replaced the stocks on all the rifles sent in, but lots of people either didn't hear about the recall, or didn't care, so lots of the salt wood stocks are still out there. I have two Browning rifles from the 1960s, but neither of them have the salt wood stocks.
