Just got finished cleaning and disassembling a 1952 pre 64 model 70 in 30-06 ser # 223xxx. Now what I remember seeing in Rule's book after 1950 all 30-06s should be stamped 3006 under the barrel. Not this one its stamped 52- 1906. Shoots like a dream also! Gotta love those pre 64 mod 70s! Let me know if I'm wrong in my assumption.