13 or 14, I built a 22 cal matchlock from scratch. I used oak for the stock, an old 22 barrel and made the rest. I cast the cock in jewlery class to look like a serpent with the match chord in his mouth. It was ugly but shot well. I used 22 cal air rifle pellets that I sized the skirt down in a die I made. I killed bunches of squirrels with it. I also did a t/c hawkin flintlock kit that year. I Killed a buck with it when I was 15.
I was shooting at age 6. Had my hunting licence at 10. I wish the current crop of kids could be doing these things rather than video games. My own son, 10 YO, likes to go hunting and fishing. He has little patience though. I can't get him interested in the work shop. I think the electronic game devices mess up their ability to have patience.