Calibre:
.222 Remington Magnum (5.56×47mm), a rimless, bottlenecked centre-fire rifle cartridge developed as a lengthened and higher-capacity evolution of the .222 Remington. It was designed to deliver higher velocities for varmint shooting and light game at extended range.

Nation:
United States.

Era:
Introduced in 1958, with peak use during the 1960s–1970s. It was later largely superseded by the .223 Remington / 5.56 NATO system, though it remains in limited specialist and collector use.

Weapon used in:
Primarily chambered in the Remington Model 700 (early variants), Remington Model 722, and a number of European sporting and target rifles following its adoption abroad. It also saw use in custom varmint rifles and early precision bolt-action builds. Despite its ballistic potential, it was overshadowed commercially by competing cartridges.

Approximate dates:
1958–1980s (mainstream and commercial use), with limited niche use continuing today

Headstamp notes:
Typical headstamps include REM 222 MAG, WIN 222 MAG, and occasional markings from European manufacturers such as RWS and Sellier & Bellot. Some early production cases may be marked simply “.222 MAG” or “222 REM MAG”. Because of its similarity in naming, careful distinction is required between .222 Remington, .222 Remington Magnum, and .223 Remington brass.

Condition notes:
Collector interest is strongest in early Remington factory ammunition and original boxed sets, particularly clean, unfired cartridges with intact primers and minimal neck marking. Brass is generally robust, but long-term storage can result in oxidation or light case dulling. Surplus or older production lots may show variation in shoulder definition due to early manufacturing tolerances.

Collector interest:
The .222 Remington Magnum is an important transitional cartridge in the development of modern high-velocity .22 centre-fire rounds. Although commercially eclipsed by the .223 Remington, it contributed significantly to the evolution of small-calibre high-performance rifle cartridges and influenced later NATO-standard developments. Collectors value early Remington production, discontinued commercial loadings, and boxed factory ammunition, while its relative scarcity compared to the .222 Remington makes it more desirable among specialist cartridge collectors and wildcat history enthusiasts.

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