I am a casual occasional recreational F-class shooter.
F-class is a version of Long Range shooting where scope sights and artificial support are allowed; instead of the peep sights and slings of Conventional target shooting or the scopes and slings of Any/Any events. It originated in Canada and has spread around. It started as a way for older shooters whose eyes were no longer sharp enough for irons and whose arthritis interfered with slings to keep shooting, but is catching on as a separate event for anybody interested.
There are two subdivisions.
F-T/R is limited to .223 or .308 caliber on a bipod with rear sandbag allowed. Weight limit is 8.25 kg = 18+ lbs with scope and bipod mounted.
F-Open guns can be of any caliber under .35 - the US national team shoots 6.5x284s - and on any rest except that it cannot have mechanical return to battery or connection between front and rear rest. Weight limit is 10 kg = 22 lbs and that does not include the front rest as long as it is not attached to the rifle.
F-class is usually conducted at the longest range available to the match; 1000 yards is desirable but there are plenty of shorter ones.
The usual course of fire is 20 shots for record and unlimited sighters in a block time of 25 to 33 minutes depending on range. There will usually be two or three such matches in a day's shooting.
For 2007, NRA has drawn up specific F-class targets to reflect the expectation of greater accuracy with scope and rest. The ten ring is one MOA and the X ring is 1/2 MOA; a ten-inch ten ring at 1000 yards. This is about half the size of the standard Long Range targets for Conventional shooters and used by F-class until the new targets became available this Fall.
There is an F-class forum and some links to NRA rules etc. at
http://www.long-range.com/forums/index.php?act=idx
