Wikipedia
Various forms of pigeon shooting exist. Most commonly used "pigeon shooting" refers to wild pigeon shooting which is part of regulated hunting world wide. It can also refer to target shooting as the targets, clay disks, are often referred to as "clay pigeons" or some times, but not often, "pigeons". Live Pigeon shooting is the sport of shooting live pigeons released from mechanical traps upon command. The word "live" is used to differentiate from regular wild pigeon hunting. Because wild pigeon hunting is regulated and has bag limited life pigeon shooting does not use wild pigeons. It was widely popular in the nineteenth century, when it was also called Trap shooting (the pigeons would be released from traps). Many countries had banned live pigeon shooting as a sport by the 1920s but the sport remains legal in multiple states in the USA, some Mediterranean countries, Spain, Mexico and some South American countries. Up until WW I live pigeon shooting was one of the great spectator sports of its time.
Live pigeon shooting used various birds in earlier times such as starlings, feral pigeons and passenger pigeon, which was thought to be the most abundant bird species ever. The modern sport of shooting clay disks is derived from it and often it is called "clay pigeon shooting". One discipline of clay pigeon target shooting is called "trap shooting" which refers to the traps of old. Another sport, helice, which launches a plastic disk with a propeller which makes the target fly erratically, is also derived from live pigeon shooting.
Live pigeon shooting is a contest whereby a live feral pigeon are released from mechanical traps upon command. The bird flies away and the shooter has two shots to kill it. Besides killing the bird it must also fall within a given area, which is delineated with a low fence of about 2 feet high, to count as a hit. The shooter stands around 24 to 33 meters from the traps on a marked sport. He gives the command "pull" and one of multiple traps opens and a pigeon is released which immediately flies away. Typically there are from 5 to 9 traps. Contests are held with Hundreds of shooters, sometimes bets take place on who will win and prize money for the winners is given at certain shoots.
In Great Britain the standard gun is the side-by-side such as the AYA #56 12 gauge firing a 2.75" cartridge with 1 1/4oz of #6 lead shot. A much heavier load than the clay pigeon counterparts.
In the USA, live pigeons shooting remains legal several states. In Pennsylvania, a 2014 bill for banning pigeon shooting was opposed by the National Rifle Association. Legislators were apparently convinced and let the bill expire. In 2015, Pennsylvania Senator Patrick M. Browne re-introduced Senate Bill 715 to amend Title 18 (Crimes and Offenses) to further provide for the offense of animal cruelty.