With the shorter sight radius of the carbine and less muzzle velocity with the shorter barrel you will be handicapped in shooting. I am sure that most of the local competitions will let you shoot with a 16” so you can get a taste of competition. Sometimes there are some shooters that will bring along a spare rifle for someone to try out the match. Some clubs will even have loaner rifles too. Most of the time the folks at the local matches will be very helpful in helping someone get started in the sport. Either you can bring your equipment with or just show up to a match and see how things work. I have found it useful to watch a match before shooting in one so you get a feel as to how things work and can focus on the shooting more than the procedures, when you do shoot a match. It also gives you an opportunity to tap into some of the knowledge of the experienced competitors.
"They say you can't use a rifle or shotgun indoors because a bad guy will grab the barrel. Yeah? Well, he better hang on, 'cause I'm gonna light him up and it will definitely be an "E" ticket ride."
"Make (your attacker) advance through a wall of bullets. I may get killed with my own gun, but hes gonna have to beat me to death with it, 'cause it's going to be empty."
Clint Smith, Thunder Ranch