I just acquired a .338-06 that is on a commercial FN action with a serial no. of 4xxx. Does anyone know where this puts it as far as date of manufacture? It would seem to be a fairly early one, but I don't even know the range of years the actions were built.

jstevens,
That's probaly a '48-'52 era rifle. If the barrel has steps and the safety is a lever on the bolt shroud, then your looking at this timeframe, probably early in that period.

Is the internal receiver collar a 'c' ring or an 'h' ring? I have a 1948 FN commercial that is a 'c' ring. The date of manufacture on mine is on the right side of the the front ring below the stock line. I 'think' FN went to the 'h' ring breeching in about 1950 or 1951. Plateau Hunter

Mine had a Douglas barrel on it when I bought it, so it isn't stepped. The safety is the wing type on the shroud I would call the Buehler type safety.

The C-ring guns will have a date of 1947 or 1948 stamped on the right side of the receiver. In about 1948, FN started the H-ring receiver, which yours probably is, given the shroud safety you describe. They switched to a smooth tapered barrel in about 1952. I've seen 48-51 serial numbers as high as 28,000, so yours is probably early in that period. Check Frank de Haas' book, Bolt Action Rifles, and Ludwig Olson's book, Mauser Bolt Rifles.