Ammo Brief: The .280 Ackley Improved



Designed by the legendary P.O. Ackley, the wildcat .280 Ackley Improved has been a mainstay for handloaders for more than half a century.

Where the .280 Ackley Improved differs from the .280 Rem.:

  • Wildcat created by the legendary P.O. Ackley.
  • Shoulder is set at 40-degrees.
  • All things equal, improves on the .280 Rem. by 100 fps.
  • Originally cases were fire-formed by shooing a .280 Rem. out of an Ackley chamber.
  • Factory loaded, starting with Nosler, in 2007.

In addition to being a famous gunsmith, barrel maker and college professor, P.O. Ackley absolutely ruled the roost when it came to creating wildcat and improved cartridges. One of his earliest was the 7mm-06 Improved, which was formed by necking down the .30-06 case and fire-forming it to less body taper and a 40-degree shoulder angle. Years later, and not long after the .280 Remington was introduced, reloading equipment maker Fred Huntington reformed its case to the Improved configuration with minimum body taper and a 35-degree shoulder angle and called it the .280 RCBS.

More Ammunition Info:

Since cases for Huntington’s cartridge could be formed by firing .280 Remington ammo in a rifle chambered for it, Ackley abandoned his 7mm-06 Improved and started chambering rifles for the .280 RCBS. But rather than staying with its 35-degree shoulder angle, he changed it to 40 degrees. And so was born a cartridge we know today as the .280 Ackley Improved.

After close to a half-century of being something only handloaders could love, the .280 Ackley Improved became a factory number, when Nosler registered it with SAAMI, started loading the ammunition and began chambering rifles for it in 2007. The Ackley version is a fine old cartridge and, when loaded with the right bullet, is big enough medicine for game up to elk and moose.

Even so, the .280 Ackley Improved is not as fast as the 7mm Remington Magnum, as a few of that cartridge’s avid supporters would have us believe. All things, including barrel length and the chamber pressure to which the two are loaded being equal, the .280 Ackley Improved is about 100 fps faster with all bullet weights than the standard .280 Remington. Cases are easily formed by firing .280 Remington factory ammo in a rifle properly chambered for the .280 Ackley Improved.

Editor's Note: This article originally appeared in the 2018 Shooter's Guide issue of Gun Digest the Magazine.


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