The 7-30 Waters is a wildcat cartridge developed by Ken Waters in 1984 by necking the .30-30 Winchester case down to 7mm (.284"). It was standardized by SAAMI and chambered in the Thompson/Center Contender single-shot pistol and rifle. The result is a flat-shooting 7mm cartridge suitable for deer hunting at ranges beyond the .30-30s practical limit, offering significantly improved ballistic coefficient from pointed 7mm bullets — impossible in tubular-magazine .30-30 rifles but fine in the Contenders single-shot design.
Type: Rifle
Introduced: 1984, United States
Parent case: .30-30 Winchester
Standardization: SAAMI
Bullet diameter: 0.284" (7.21 mm)
Case length: 2.04" (51.82 mm)
Overall length: 2.55" (64.77 mm)
Max pressure: 52,000 PSI
Rim type: Rimmed
Primer: Large Rifle
Typical twist rate: 1:10
Muzzle velocity: 2700–3000 fps
Muzzle energy: 1943–2398 ft-lbs
Effective range: 300 yd
Common bullet weights: 120, 139 gr
Primary use: hunting_medium_game, hunting_small_game
Production status: Discontinued
Also known as: 7/30 Waters
History: Ken Waters was a gun writer and handloader who developed the cartridge for the Thompson/Center Contender platform, which allows pointed bullets since there is no tubular magazine. The Contender pistol in 7-30 Waters became a popular deer hunting handgun in the 1980s and 1990s. SAAMI standardization enabled factory ammunition from Federal and Winchester. Production ceased as the Contenders market…
Notable firearms: Thompson/Center Contender, Thompson/Center Encore