The answer to your question is 1967, according to this source: www.coltautos.com/default.asp
No one knows anything about your gun until you tell us a little more about it. Rifle, pistol, revolver, shotgun? Any names marked on it?
the micro groove is button cut and ballard is the lands and grooves are not equally spaced
It's a 1913 gun, but much more information is needed. What gauge, barrel length, ribbed barrel (if any), and most important - condition. Value is $300-$1500. email@example.com
A few different models of the Visible Loader were offered between 1907 and 1932. Mainly differing only in the sights. Truly excellent condition rifles can reach $350-$400. firstname.lastname@example.org