For the air rifle competitions, it starts with the Divisions...then within these Divisions are PCP and Piston classes. Sqwirl covered nicely some of the differences between Divisions in his post #2.
Here's a link to the AAFTA rule book if you want a detail read regarding what you can and cannot do in each Divisions.
Here's the break down according to AAFTA
AAFTA Division Rules Competitors shoot in one of three divisions:
Open, Hunter, or World Field Target Federation (WFTF) Division. These divisions offer classes typically based on power plant. Restrictions in each Division are intended to limit the means of support of the gun, and to ensure safety and fairness in competition.
If questions arise about the class a shooter will compete in, the Match Director shall have the final say.
Open Division The Open Division rules are intended to promote diversity and innovation to advance the state of the art in the sport of Field Target. See section on Open Division Rules.
Hunter Division The Hunter Division rules are intended to promote accessibility to the sport of Field Target, and the use of typical hunting equipment. As such, the rules shall enforce limits on the type of allowed equipment and shall allow for a broad range of competitor physical fitness and conditioning. See section on Hunter Division Rules.
World Field Target Federation (WFTF) Division The WFTF Division rules are intended to promote International style Field Target competition, and as such shall closely resemble the World Field Target Federation (WFTF) Core Rules. See section on WFTF Division Rules.
Classification Standard Classes
The hosting club will typically offer PCP and Piston classes for the Rifle Divisions, and Limited and Hunter classes for Pistol. The minimum number of shooters required for Place Awards at Nationals is five, and three at Regional or Grand Prix matches.
Additional Classes
The hosting club may offer additional classes based on level of expertise, age group or other criteria. These classes are generally offered if there are at least three shooters per class. For example, Junior or Senior classes. Match Directors should announce additional classes prior to the match, whenever possible.
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Here are the majority of pistol rules according to AAFTA. Just a Heads Up, most clubs do not offer pistol matches as a regular part of their monthly competition (please chime in if your club is the exception). Pistol matches are a completely different venue and usually offered on most Grand Prix and US nationals (usually shot on a Friday, and I've also seen it switched to Saturday afternoon due to logistics).
Pistol Field Target Rules
- Air pistols only. The maximum caliber is 0.25.
- Muzzle energy limited to 12 foot-pounds.
- Barrel length is limited to 15 inches including any attachments to the muzzle (e.g. moderator, or flip
compensator). A wooden or other barrel-friendly dowel will be used to determine the length of the
barrel, as measured from the tip of the barrel or muzzle attachment to the breech-face. - Fore end depth is limited to a maximum of 3 inches, measured from the center of the barrel to the
lowest part of the gun forward of the trigger guard. - Attached cylinders at the rear of the Pistol are not allowed.
- Overall length including any attachments must not exceed 25 inches.
- No shooting jackets, slings, harnesses, or other bodily supports. Clothing or shooting gloves worn by
the shooter must not restrict hand or body movement. - No shooting sticks or mono/bi/tripods.
- Kneepads may not exceed 1 inch in thickness. The intent is to allow comfort, and not an extra form of
support. - Sandbags, knee risers or butt stocks are not allowed.
- Scopes maximum magnification of 12x. Variable scopes capable of greater than 12x are not allowed.
Clicking is allowed. - Seats up to 6 inches high allowed.
- Time limits may be enforced.
- Any shooting position is allowed so long as the pistol is fully supported by the competitor. Hangy-
tanks are allowed but cannot contact the ground or shooter’s anatomy while shooting. - Distance 10-35 yards
- Kill zones sizes shall be 0.5” to 2” in diameter.
- Forced Offhand (Standing) Shots: Pistol is held solely by the hands, and may not contact the arms,
body, or any other kind of support. - Eyecup contact with the face is permitted.
- Classes: AAFTA requires at least one sanctioned class for a legal match. Other classes may be
added if desired. Sanctioned classes are:- Limited Class: Rules as defined above.
- Hunter Class: Rules as defined above, but no turret adjustment allowed during the match (no
clicking.). Any form of seat without back or arms support may be used. Monopods, shooting
