The AW system is almost unique in being a purpose-designed military sniper rifle, rather than an
accurised version of an existing general-purpose rifle. The modular design of the AW system allows for flexibility, serviceability and repairability under field and combat conditions. Major components, such as the barrel and the bolt, can be switched between rifles, or replaced in the field by their operator with the help of some tools. The chambering can also be switched by the operator as long as the barrels, bolts and feeding mechanism can handle the shape and size of the cartridges.
Features equipped with an Arctic Warfare rifle Rather than a traditional wooden or
polymer rifle stock, the AW is based on an aluminium chassis which extends the entire length of the stock. This chassis system is marketed as the Accuracy International Chassis System (AICS) and can be used for all Accuracy International rifles. All other components, including the receiver, are bolted directly to this chassis. Two hollow polymer "half thumb-hole stock panels", usually coloured green, dark earth or black, are in turn bolted to each other through the chassis, creating a rugged yet, for its sturdiness, comparatively light weapon. The Accuracy International
receiver is bolted with four screws and permanently bonded with epoxy material to the aluminium
chassis, and was designed for ruggedness, simplicity and ease of operation. To this end, the heavy-walled, flat-bottomed, flat-sided receiver is a stressed part, machined in-house by AI from a solid piece of forged carbon steel. AW rifles are supplied in two action lengths—standard AW (short) and long SM (magnum). The six bolt lugs, arranged in two rows of three, engage a heat-treated steel locking ring insert pinned inside the front bridge of the action. The ring can be removed and replaced to refresh headspace control on older actions. The AW system cast steel bolt has a diameter combined with gas relief holes in a diameter bolt body and front action bridge allowing high-pressure gases a channel of escape in the event of a cartridge-case head failure. Against penetrating water or dirt the bolt has milled slots, which also prevent freezing or similar disturbances. Unlike conventional
bolt-action rifles, the bolt handle is bent to the rear, which eases the repeating procedure for the operator and reduces the contour of the weapon. The action cocks on opening with a short, 60 degree bolt throw and has a non-rotating (fixed) external extractor and an internal ejector. Firing pin travel is to keep
lock times to a minimum. Finally, an integral
dovetail rail located above the receiver is designed to accommodate different types of optical or electro-optical sights. As an option, a
MIL-STD-1913 rail (Picatinny rail) can be permanently pinned, bonded and bolted to the action, providing a standard interface for many optical systems.
Ammunition feeding Cartridges are fed through the bottom of the receiver using a detachable, double-stack, steel
box magazine. Rifles chambered for .300 Winchester Magnum or larger use a single-stack magazine. Alternatively cartridges can be loaded singly directly into the chamber if no rounds are present in the magazine.
Barrel The
free-floating, heavy, stainless steel
barrels (stainless steel resists throat erosion better than normal barrels) for the available cartridge chamberings all have a different length, groove cutting and
rifling twist rate optimised for their chambering and intended ammunition. For
.243 Winchester, the twist rate is 254 mm (1 in 10 in), and for
.308 Winchester/
7.62×51mm NATO variants it is 305 mm (1 in 12 in), except for the suppressed-barrel variant. If the consistent accuracy requirement of an operator is no longer met, the barrel can fairly easily be renewed. This is normal practice for active high-performance precision rifle operators, who regard barrels as replaceable. The barrels are provided by Australian company Maddco Rifle Barrels (button rifled), and Scottish company Border Barrels, who cut-rifles them on Pratt & Whitney rifling benches. Twists are one turn in 10, 11, 12, 13 and 14 inches for 7.62 MM depending on RFP.
Safety A three-position, firing pin blocking
safety lever on the bolt shroud allows the bolt to be manipulated with the safety on. If the weapon is cocked, the firing pin can be felt at the end of the bolt action, making it possible in poor visibility to feel whether the weapon is ready to fire. The safety-catch of the weapon is also positioned at the rear, showing white if the safety is on, red if not.
Trigger The two-stage
trigger mechanism has an adjustable trigger pull weight of 10 to 20 N (2.2 to 4.4 lbf). The trigger assembly can be easily removed for cleaning by undoing two socket-head cap screws.
Accessories The AW is usually equipped with an integrated
bipod and it also has a monopod mounted on the buttstock. Accuracy International accessories for the Arctic Warfare system include a selection of PM II series telescopic sights made by
Schmidt & Bender with laser filters for the military scopes, aluminium one-piece telescopic sight mounting sets,
MIL-STD-1913 rails (Picatinny rails), lens hoods, various optical and kill flash filters and lens covers for telescopic sights, auxiliary iron sights for emergency use, cleaning kits, muzzle brakes/flash-hiders and
suppressors, butt plates and spacers to regulate the
length of pull and butt angle to the requirements of the individual shooter, buttspikes, bipod (adapters), handstops, mirage bands, soft and heavy-duty transit cases and various maintenance tools. == Accuracy International Chassis System ==