@jonnyc: The remington 700 bolt which I measured did not have a j lock. The shroud with the j lock is about 1/4 inch longer, and so if you correct for that, then the measurements correspond to a remington 700, short action bolt. Again, I believe scorch got it right in post #3.
@44AMP: Although there is some confusion about the starting date, I think j-lock use started in 2002 and ended with 2005 production, inclusive. My 700 classic in .221 fireball was issued in 2002 and it had the j-lock. It was replaced with a PTG firing pin and shroud assembly. That got rid of the j-lock and the snakey firing pin spring. Gre Tan, David Tubb, and PTG all offer remington 700 firing pin assemblies to replace the j-lock assembly.