I finally got a Savage 99 in 300 savage. She was built in 1937 based on the serial number but the lever boss is a Z (not in a circle). The Z isnt listed on the unofficial Savage 99 websites and I was wondering if anyone knew what it meant? There is also an SB in a circle stamped on the left side of the barrel behind the calibre mark and a 7 stamped on the barrel under the fore arm. Does anyone know what these stand for? Thanks in advance.