Interesting stories.
My first was at 15 years old back around '63, from a rifle I built myself using plans I found in a Popular Mechanics or Mechanix Illustrated magazine. Used a 2-groove barrel from an '03-A3 Springfield I bought surplus for $3.95, and a lock from Dixie Gun Works. I had to use rubber bands stretched between the hammer spur and the drum to fire my homemade caps, which consisted of 2 or 3 cap pistol caps stuffed into a fired .22LR case.
The thing was neither accurate nor beautious to behold but it was MINE. Dad would have never allowed me to buy one (couldn't have afforded it anyway), but he never complained about my having one I made.