The world governing body for muzzle loading is the Muzzle Loaders Associations International Committee (MLAIC) and since 1999 has held Long Range World Championship, with competitions fired at 300, 500, 600, 900 and 1000 yards. More information from: www.mlaic.org
The Dominion of Canada Rifle Association (DCRA) was founded in 1868 to promote and encourage the training of marksmanship throughout Canada. The Canadian Black Powder Championships include events for both muzzle loading rifles and black powder cartridge rifles. More information from: www.dcra.ca
United States of America
The National Muzzle Loading Rifle Association (NMLRA) was founded in 1933. Their mission statement says they "to promote, support, nurture, and preserve NMLRA’s and our nation’s rich historical heritage in the sport of muzzle loading through recreational, educational, historical, and cultural venues such as match competition, hunting, gun making and safety, historical re-enactments, exhibits, museums, libraries, and other related programs." Some of their events include long range muzzle loading competition out to 1,000 yards. More information from: www.nmlra.org
The United States International Muzzle Loading Committee is a non-profit corporation created in 1976 to recruit the best shooters possible from the US muzzle loading community to become members of the United States International Muzzle Loading Team and compete in the MLAIC World Championship Events. For long range team news see: www.usimlt.com/Longrange.html
Note: Can any provide information on other national governing bodies that deal with long range muzzle loading? Please contact Research Press.