Rifle shooting is divided into three basic categories: smallbore, bigbore, and air rifle. These are determined by the type of rifle used, and there are further subdivisions in competition shooting based on the type of shooting position used (prone, kneeling, and standing). The competitor who records the highest score with his total of shots wins the competition.

Competitors shoot in line, shoulder to shoulder, and there must be enough space behind them for officials and spectators. The targets are numbered to correspond with the firing points.
Sighting (or practice) targets are clearly marked and may be removed during the competitive shooting.
Outdoor targets are fixed so as to remain stationary even in high winds; wind flags are placed 10m in front of the competitors.
Behind the targets there must be bullet catchers, and an earth wall or adequate dead ground.
Distances are measured from the target face to the firing line, where the competitor may place his forward foot or elbow.
Clocks are used to inform competitors of remaining shooting time.

10m range: indoor or outdoor. The target height is 1.5m above the level of the shooting station and may be adjusted to the competitor’s height. The background must be light-coloured and non-reflecting. Horizontal deviation from an angle of 90° may not exceed 25cm. The competitor usually changes the targets himself.

50m range: indoor, semi-indoor, or outdoor. The optimum target height above the level of the shooting station is 50cm. Horizontal deviation from an angle of 90° may not exceed 1m.

300m range: the line of targets can be lowered into a covered pit and the range may be surrounded by walls for security. The optimum target height above the level of the shooting station is 3m. Horizontal deviation from an angle of 90° may not exceed 6m.

50m distance
smallbore rifle events:
diameter 154.4mm
“bull” diameter 10.4mm

10m distance
air rifle events:
diameter 45.5mm
“bull” diameter 0.5mm

300m distance
big and smallbore rifle events:
diameter 1000mm
“bull” diameter 100mm

Smallbore free
Maximum weight: 8kg
Maximum calibre: 5.6mm for rimfire (0.22)
The right-hang grip must not rest on the sling or the left arm.
Maximum length of the hook of the butt end is 15.3cm. The stock or butt end must not give special support against the body. The butt plate has a maximum adjustment of 3cm.

Smallbore standard
Maximum weight: 5kg
Maximum calibre: 5.6mm
Thumb holes, spirit levels, hand stops, and thumb, palm, or heel rests are forbidden.

Bigbore, free and standard
Maximum calibre: 8mm
Minimum trigger weight (bigbore standard): 1500g.
Other specifications as for smallbore.

Air rifle
Any compressed air or CO2 rifle, of conventional appearance and 4.5mm calibre.
Dimensions and prohibited features as for smallbore standard.

Sights
No lens, lens systems, or telescopic sights are permitted. Correcting glasses, if needed, may be worn by the shooter.

Smallbore free: English match 50m
60 shots prone, and 15 sighting shots;
or two series each of 30 shots and 10 sighting shots.
Duration: full match 120 minutes; half match 80 minutes.

Smallbore free: three position 50m
120 shots: 40 prone, 40 standing, 40 kneeling; and 10 sighting shots for each position. (The 40 shots prone may be combined with the first 40 shots of an English match.)
Duration: prone, 90 minutes; standing, 120 minutes; kneeling, 105 minutes.

Smallbore standard 50m
60 shots: 20 prone, 20 standing, 20 kneeling; and 6 sighting shots for each position.
Duration: 150 minutes.

Air rifle 10m
60 shots standing, and 10 sighting shots.
Duration: 120 minutes.

Bigbore free 300m
120 shots: 40 prone, 40 standing, 40 kneeling; and 10 sighting shots for each position.
Duration: prone, 90 minutes; standing 120 minutes; kneeling, 105 minutes.

Bigbore standard 300m
60 shots: 20 prone, 20 standing, 20 kneeling; and 6 sighting shots for each position.
Duration: 150 minutes.

Unless each competitor has his own target, the maximum time allowance for a four-man team is:
smallbore free (three positions), 21 target hours;
smallbore standard, 10 target hours;
bigbore standard, 10 target hours.

Air rifles: maximum calibre 5.6mm; steel projectiles are forbidden.
Smallbore: lead or similar soft material.
Bigbore: tracer, armour piercing and incendiary ammunition are forbidden.

http://www.nzshootingfed.org.nz