good question, well the sport would have to be along the lines of speed, agility, strength that best suits it. For example: high jump, it's the best sport that can be used for strength in your legs...
The main thing and also the best is just to practice practice practice find something you enjoy not whats popular or looks cool. People who enjoy something will find it is easier to practice it and...
Probably, the day after someone invented the first gun, but to answer what you probably want to know, in 1872, the year after it was formed, the NRA began the first organized national matches.