Can only speak for the Machinist trade, but I completed a certified apprenticeship which consisted of 4 yrs @ (2,000 hrs/yr shop time + 4 yrs @ 160hrs/yr classroom time. After succesful completion we were then issued a Journeman's card by the Dept of Labor. Unfortunately the shops I was in advancement to a Master as often as not involved more "Politics" than abilities. I sincerely hope it was not that way in the gunmakers trade.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra