Ammo Brief: The Groundbreaking .204 Ruger

The first .20-caliber produced in a large scale, the .204 Ruger arms shooters with a red-hot varminting round.

• The .204 Ruger was the first .20-caliber cartridge produced on a large commercial scale.
• Accurate, with a mild recoil, the .204 Ruger also offers excellent barrel life.
• The parent case of the .204 is a .222 Remington Magnum.
• It is necked down and given a 30-degree shoulder angle.
• The .204 performs best when shot out of a 26-inch barrel with a 1:12 twist.

Introduced in 2004 as a joint Hornady-Ruger project for varmint and target shooting, the .204 Ruger became the first .20-caliber cartridge to be produced on a large commercial scale. Remarkably, it also offers excellent barrel life. After shooting approximately 500 prairie dogs with the Ruger and Dakota rifles chambered for the .204 Ruger, a former contributing editor to this book found it to be an accurate, low-recoil round, superbly suited for long-range varminting. The .204 Ruger received the Academy of Excellence 2004 Cartridge of the Year Award.

The 204 Ruger uses the 47mm-long .222 Remington Magnum as its parent case, necking it down to accept .204 bullets and changing the shoulder angle to 30 degrees. It performs best with 26-inch barrels using a 1:12 rifling twist. The cartridge is available in Ruger, Dakota, Remington, and Savage bolt-action rifles, Thompson/Center and SSK Industries Contender single-shot rifles, and AR-15 style rifles. Hornady, Remington, and Winchester offer loaded ammunition.

Editor's Note: This article is an excerpt from Cartridges of the World 15th Edition.