Go to your saved Cartridges

Your Armory

  • Your Armory is empty.

Can't find what you're looking for? Open a ticket and we will help you find it!

280 Ackley Improved

280a

In 2008, Nosler standardized Parker Otto (P. O.) Ackley’s version of the 280 Remington. As with all AI designs, the 280 AI shares Ackley’s reduced case body taper (0.001-inch per 0.1-inch of body length, which, in this instance is about half what the parent case had,) and sharper shoulder (in this instance, 40-degrees versus 17½-degrees). The one distinction: the 280 AI is now a standard SAAMI chambering.

Layne Simpson and others had long worked toward making this happen. Finally, only half a century after Remington introduced the 280 and Ackley immediately improved the design, the mainstream gun industry has seen fit to honor Mr. Ackley for his outstanding work toward improving the art.

Loaded to the same pressure as the 270 Winchester, 65,000 psi, which is as high as any mainstream SAAMI chambering uses, 280 AI performance is far better. Performance of the 280 AI comes very close to matching performance of the 7mm Remington Magnum.

 


 

When both are loaded to SAAMI specification pressure, using the best modern propellants, the velocity difference is about 50 fps, which is of questionable value (see below). Because of the significantly heavier charge required for the 7mm Rem Mag to get full velocity, recoil difference is about 14%, which is certainly significant.!

Compared to the 7mm Rem Mag, the 280 Remington AI uses less propellant and burns that more efficiently by trapping more in the chamber and accelerating less unburned propellant down the bore. These advantages matter: recoil is noticeably less, barrel heating is less, and barrel life is greater.

Five 280 AI rounds fit in a typical magazine compared to three 7mm Rem Mag rounds. The conventional rimless case of the 280 AI is much easier to load into a box magazine and feeds from that and into the chamber more smoothly. Some of us believe these advantages more than offset the modest ballistic deficit and therefore consider the 280 AI a better choice than the 7mm Rem Mag.

Heritage of this case dates to the 1870s with the introduction of the 40-70 Ballard case.


The text associated with the cartridge description reflects opinions and conclusions of the author, M.L. (Mic) McPherson. Lee Precision and its employees do not necessarily either agree or disagree with any of his comments. We present these with due deference to his recognized expertise in the firearms field. His acumen extends to handloading and all aspects of ballistics - internal, external, and terminal.
Die Sets
Lee Collet Necksizing 2-Die Set
Lee RGB Die Set
Lee Full-Length Sizing Die Set
90989 (3-Die set)
Lee Breech Lock Die Set
Lee Ultimate 4-Die Set
Lee Loader
Single Dies
Full-Length Sizing Die
91123
Sizing Die
Neck Sizing Die
91013
Undersize Sizing Die
Charging Die
90194 (Long Charging Die)
Seating Die
Factory Crimp Die
90841 (Collet Style)
Taper Crimp Die
Inline Bullet Feed Die
Die Accessories
Guided Decapper
Undersized Flash Hole Decapping Mandrel
Undersized Mandrel
Case Conditioning Tools
Case Length Gauge and Shell Holder
90166
Quick Trim Die
91375
Presses
Reloader Press (50 RPH)
Hand Press (50 RPH)
Challenger Press (50 RPH)
Classic Cast Press (50 RPH)
Value Turret Press (250 RPH)
Classic Turret Press (250 RPH)
Ultimate Turret Press (250 RPH)
Pro 1000 Press (500+ RPH)
Pro 4000 Press (500+ RPH)
Six Pack Pro Press (500+ RPH)
Shell Plates and Holders
Priming Tool Shell Holder
90202 (#2)
Universal Press Shell Holder
90519 (R2)
X-Press Shell Holder (APP)
91535 (#2)
Pro 1000 Shell Plate
Auto Breech | Pro 4000 Shell Plate
90584 (2)
Six Pack Pro Shell Plate
91836 (2L)
Inline Bullet Feed
Inline Bullet Feed Die
Inline Bullet Feed Kit
Inline Bullet Feed Magazine
Bullet Casting
Classic Bullet Sizing Kit
Breech Lock Bullet Sizer and Punch
Bullet Molds

Challenger III

From $117.00

Ultimate Turret Press

From $320.00

Deluxe APP Press Kit

91898

The Lee Deluxe Automatic Processing Press gives you the same priming convenience found only on expensive progressive reloading presses.

$155.00

Six Pack Pro Press

From $400.00