Fullbore target rifle

Fullbore target rifle (TR) is a distinctively British and Commonwealth of Nations shooting discipline that evolved from Service rifle (SR) shooting in the late 1860s, and is governed in the UK by the rules of the National Rifle Association, UK (NRA). Similar rules are used in several Commonwealth countries, but the issue in 2006 of the rule book of the International Confederation of Fullbore Rifle Associations (ICFRA) has provided an alternative basis for the administration of the sport.

Modern target rifles are extremely accurate, and have aperture sights which are fully adjustable for elevation and windage. They developed from the observation that the eye when viewing through a circular aperture will naturally centre the black circular target, on a white backing. Initially this was accomplished using a standard 'post' foresight at the muzzle of the rifle, which over time developed into a tube with a circular ring aperture so that the black 'bull' would be viewed within the foresight ring which in turn was centred in the rear aperture. This arrangement improved the accuracy as the sight distance was increased with the aperture sight closer to the marksman / woman than that of the military 'iron' rear leaf sight fitted directly to the barrel.

To level the playing field as much as possible without stifling progress, and to make it possible for riflemen of all budgets to compete seriously, the rifle or all its component parts must be 'readily available in quantity'.

Fullbore Target Rifle involves prone position single shot precision shooting using adjustable aperture sights at 'round bull' targets at distances from 300 to 1000 yards, with each shot being carefully scored and analysed. The usual calibre used was .303 British (standard military) up to the late 1950s when the NATO countries adopted the .308 Winchester/7.62×51mm NATO as the new military interoperable choice of ammunition. The .303 British calibre is still in use by Service Rifle shooters and was exclusively used by Fullbore in the Short, Magazine Lee–Enfield (SMLE) No.1 Mk. III an No. 4 rifles. Often this aspect is forgotten or overlooked.

...
Wikipedia