
The venerable Encyclopedia Britannica defines the law of diminishing returns as an “economic law stating that if one input in the production of a commodity is increased while all other inputs are held fixed, a point will eventually be reached at which additions of the input yield progressively smaller, or diminishing, increases in output.” Generally speaking, in more colloquial terms, the law of diminishing returns simply refers to a scenario in which the investment required to maintain a steady increase in a rifle’s accuracy, persay, begins to take on an exponential cost. In other words, it is the law that governs why it can cost $500 to double a rifle’s accuracy from 4 MOA to 2 MOA, but doubling the accuracy again from 2 MOA to 1 MOA can cost $2000 or more.
Which brings us to the $22,000 dollars’ worth of gun pictured here.
Now, obviously that price tag includes the optic and accessories, but nonetheless the Accuracy International AXMC rifle pictured here is undeniably expensive. In fact, unless you have just a hair over $8,000 to spend on your next rifle, this won’t be it. Having debuted at SHOT Show in 2014, the AX line of rifles are Accuracy International’s first kick at the multi-cal, barrel-swapping can and as such are some of the most expensive rifles in their lineup. Within the AX line there are three disparate models; the long-action AXMC (AX multi-cal), a short-action AX-308 model with the same quick-change barrel system, and an AX-308 with a conventional fixed barrel. To differentiate between these various models, the multi-calibre models have become commonly known as the AX-338MC and AX-308MC, while the fixed barrel model is generally referred to as the AX-308. Obviously, due to the length of the action and magazine well, the AX-338MC can accept both long-action calibres such as 300 Win Mag, as well as short-action calibers, and our test rifle shipped with both a .338 Lapua barrel, bolt and magazine as well as a .308 barrel, bolt and magazine. The AX-308MC is limited to rounds commonly available in short-action tactical rifles, and barrels can be found in a variety of calibre if one looks hard enough, or conversely can chambered for any other round that can fit the AX-308MC’s .308 bolt face.


The most obvious difference between the AXMC and most previous Accuracy International rifles is the chassis-style format. Having made their name using a more conventional rifle-in-stock arrangement, the AXMC’s tubular handguard and skeletonized stock looks thoroughly modern, and offers many benefits to those that need to mount additional accessories to their rifles. With an uninterrupted top rail, soldiers and law enforcement officers can mount night vision optics cleanly and easily in front of their standard optic, while the KeySlot accessory rails at 3-, 6-, and 9-o’clock allow additional lengths of picatinny rail to be mounted where the user needs them for bipods or other accessories.
Now, a note on KeySlot: It is not KeyMod. KeyMod accessories are not compatible with Accuracy International’s patented KeySlot system. Although predating the development of KeyMod, KeySlot remains the intellectual property of Accuracy International, which has ensured it remains far less common than the open source KeyMod system. This means all AXMC owners should expect to turn to Accuracy International for their accessory rails. This means all AXMC owners should expect to pay a pretty penny for their accessory rails. Wait; did I just say the same thing twice?
But while the handguard may be the most obvious departure from Accuracy International’s previous rifles, the big party piece is a small machine screw located at the front of the action. Loosening this screw with an allen wrench that stows handily in the cheek rest releases the action’s grip on the barrel. With that done, removing the barrel is as easy as simply unthreading it from the receiver, and sliding it out of the handguard. Installation of a new barrel is simply the reverse. Headspacing is handled by a large shoulder machined into the barrel shank that butts up against the front of the receiver. Tightening the machine screw again secures the barrel in place. If the calibre’s base diameter is changing (in our case from .338 Lapua to .308 Winchester), then the bolt is also removed and replaced with the correct bolt, as is the magazine and associated magazine well insert. The entire process takes no more than a few minutes if done methodically, and although there is some degree of POI shift it is not dramatic (in our case little more than a few MOA) and more importantly, proved 100% consistent. In other words, our POI shifted the exact same way every time I switched barrels, meaning that I could switch from .338 Lapua to .308 Winchester, dial in the expected POI shift, and bang targets on our first shot.

Which brings us to the good part: The shooting. Obviously shooting any Accuracy International rifle is a proper first rate treat; these things are the veritable Ferrari’s of the long range world. And to shoot the top of the line AXMC model? Well, that’s one of those experiences that mixes excitement with trepidation, if only due to the overall price tag of the thing you’re putting up to your shoulder. After all, it’s not every day one gets to shoot a gun worth more than the average economy car.


So what makes it so accurate? Well there’s obviously the mechanical benefits of a gun that’s been assembled by a team of engineers of the ilk that Accuracy International employs. But we’ll talk about that later. The other component to this gun’s supreme accuracy is the way Accuracy International has considered the human element in a way many gun manufacturers don’t. The pistol grip is perfectly formed to grip your hand just as much as it was designed to be gripped. That lets you keep a relaxed hand on the controls, keeping any wayward muscle tension from effecting your aim. Likewise, all that adjustment in the stock makes sure your shoulder and head support the gun with your natural skeletal structure and shape, rather than requiring your body contort around the gun and be forced to use muscle to support the rifle. The massively heavy barrel profiles on both the .338 and .308 barrels, and the huge muzzle brakes fitted quell almost all recoil to the point that the rifle moves so little that even an inexperienced shooter is naturally able to watch their round’s impact through the optic. And the trigger… well… although it’s not quite conventional (due to the manner in which it adjusts, the trigger has a lot of overtravel) it is perfectly suited to the task at hand. With a smooth swing through the first stage and a nice, clean, light break it somehow naturally encourages the shooter to concentrate on a gentle squeeze. Don’t ask how a trigger can make you remember to practice proper trigger control… just know that somehow, Accuracy International figured out how to do exactly that.

As a result, the AXMC is in many ways the physical embodiment of the law of diminishing returns. For many civilian shooters and even some professionals, the incremental steps Accuracy International has taken towards absolute reliability and perfect precision do not justify the expense incurred in the pursuit of those lofty goals, and for those shooters there is all manner of Savage, Remington, and even Sako rifles (not to mention dozens of other, smaller manufacturers). But for the shooters that cannot accept the notion of compromise, the work Accuracy International does with rifles such as the AXMC is as indispensable as it is invaluable. And while I hope to never find myself in the situations faced by those sorts of individuals, shooting a rifle as incredible as the AXMC provides a brief glimpse into precisely how awesome something can be when the law of diminishing returns are absolutely and utterly ignored.