is anyone knowledgeable about ss contract mausers, i have a large font BNZ 43 Mauser i received in a trade and i am trying to verify it is a SS contract gun, it has a 3 digit serial number, no letter code, , one eagle- cross stamp, and one waffen proof on it. appears to be the remnants or incorrectly SS lightning bolt stamped on the right side of the receiver by the bolt handle