I recently bought a Remington 511X. I need help determining if this rifle is a one of a kind. The date code is AL - which means that it was made in March of either 1942 or 1964. Next to the date code are the numerals 31 or 34, I can't tell. I tend to believe it was '64 because of the font of the lettering on the barrel and Remington and Scoremaster are side by side. Also, the 511 A & P were discontinued in 1963. But the 511X was introduced in 1965 and production ended in 1966. But that doesn't help me because the oldest date that this rifle could be is 1964. The stock appears to have Remington custom checkering and it doesn't appear to ever had iron sights (though the barrel has screws in place where the sights should be. The top of the receiver is grooved and it came with Weaver rings. The gun looks almost new. Could I have the prototype of the 1965 production line of 511X's?