Nosler .280 Ackley Improved
By Chuck Hawks
Sponsored by Nosler, P.O. Ackley's .280 Remington Improved has become a SAAMI standardized rifle cartridge. .280 Ackley Improved factory loaded ammunition and unprimed brass for reloaders became available from Nosler in 2008.
Long a popular wildcat (there is an article about the .280 Rem. Ackley Improved on the Wildcat Cartridges page), the .280 AI is based on the .280 Remington case blown-out by fire forming for a modest increase in case capacity. In addition to leaving very little body taper, Ackley increased the shoulder angle of his improved version of the .280 from the original 17.5 degrees to a radical 40 degrees. The net result of all of this is a velocity increase with maximum loads of about 100 fps. Like the .280 Remington, the .280 AI has a standard .473" rim diameter and requires a standard (.30-06) length rifle action.
If necessary, a rifle chambered for the Nosler .280 Ackley Improved can safely fire .280 Remington ammunition. This might matter if your .280 AI ammo goes astray on an out of state hunt and a local sporting goods store happens to stock .280 Remington cartridges. The rifle would need to be re-zeroed for the slower load, of course.
The .280 Remington has never become particularly popular, but it has hung around since its introduction in 1957 and shows no signs of fading away. The .280's marketing problem has always been that it was introduced three decades after the .270 Winchester and offered no improvement in performance. Nosler's .280 Ackley Improved does offer an improvement over both the standard .270 and .280 cartridges, but falls well short of the very popular 7mm Remington Magnum. It is actually about midway between the standard .280 and the 7mm Mag. in performance
Whether consumers will consider this a "gap" worth filling remains to be seen. I rather suspect that .270 Winchester and .280 Remington fans will remain content with their favorites and those looking for higher velocity in a standard length action will be more likely to take the full step up to one of the 7mm Magnums, rather than settle for a half step up to the .280 AI, but I have been wrong before.
For 2008, Nosler is chambering their Limited Edition Custom rifle in .280 Ackley Improved. Only 500 of these rifles will be made. If you are hankering for a .280 Ackley Improved rifle, the price of one of these fine Noslers is $3995, which includes a mounted Leupold Custom Shop VX-III 3.5-10x40mm riflescope.
With excellent, but very expensive ($57.95 for 20 rounds in 2008), Nosler Trophy Grade ammunition using a 140 grain AccuBond bullet at a MV of 3150 fps as the only available factory load and a single run of only 500 $4000 rifles, the .280 Ackley Improved stretches the definition of "commercially available" to the breaking point, yet it is now a SAAMI standardized cartridge. Only time will tell if it will become available in a true factory built rifle and if popular priced ammunition will be offered in the caliber.
Certainly the .280 Ackley Improved is a potent all-around type cartridge. It can use any standard 7mm (.284" diameter) bullet, but projectiles weighing at least 139-145 grains would seem to be most suitable for its case capacity and its purpose as a big game hunting cartridge. Other useful bullet weights would be 150-154 grains and 160-162 grains.
The Fifth Edition of the Nosler Reloading Guide shows that Nosler 140 grain bullets can be driven to a muzzle velocity (MV) of around 3150 fps by several medium/slow burning powders. The Nosler technicians found IMR 4831 to be the most accurate powder in their test rifle's 24" barrel. 54.5 grains of this powder gave a MV of 2920 fps, while a maximum load of 58.5 grains yielded a MV of 3164 fps.
According to the Nosler Reloading Guide, their 150 grain bullets can be driven to approximate velocities between 3000 and 3100 fps by maximum loads of appropriate powders. With this bullet weight, H4831sc powder provided the best accuracy in their test rifle. 56.5 grains gave a MV of 2776 fps and a maximum load of 60.5 grains of H4831sc achieved a MV of 2994 fps.
Nosler 160 grain bullets can be driven to a maximum MV of about 2850-2950 fps. With these bullets, AA3100 powder provided the best accuracy in Nosler's test rifle. 54.5 grains yielded a MV of 2708 fps, while a maximum charge of 58.5 grains resulted in a MV of 2903 fps. All of these Nosler loads used reformed Remington .280 brass and Federal 210 primers.
If I had a Nosler .280 Ackley Improved rifle, I'd choose the 140 grain Ballistic Tip bullet for long range hunting of CXP2 game. For mixed bag hunts (deer and elk, for example) it would be hard to beat the 150 grain Partition, which is also the bullet of choice in my Merkel K3 7mm-08 rifle. Push the .280 AI to its limit by developing a load specifically for use on large CXP3 game and the 160 grain Partition would be an appropriate choice.
The .280 AI is a viable all-around cartridge for the reloader who can afford to buy a custom built rifle. We will have to wait and see if becoming a SAAMI standardized cartridge gives its popularity a shot in the arm.
Copyright 2008, 2015 by Chuck Hawks. All rights reserved.