It's no wonder that the AR-15 rifle, in all its incarnations, has become so dominant in the law enforcement patrol rifle market. It's lightweight, accurate, possesses little recoil, is easy to maintain, and has plenty of capacity.
Yes, the standard versions of the M-16 and M-4 have proven to be useful tools for a variety of police applications. But there are times when an officer could use a little more help. That's why there have been a number of recent efforts to improve the performance of both the 5.56mm NATO cartridge and the nearly identical .223 Remington cartridge. Improved ballistics and penetration at extended distances have been achieved by loading these cartridges with heavier bullets.
Still, there are times when a .223, regardless of bullet weight, just doesn't cut it. Sometimes you need more power downrange. For example, not long after our special forces hit the ground in Afghanistan they started asking for more .308 rifles that could neutralize distant targets across windy canyons.
The .308 Winchester cartridge, also known as the 7.62mm NATO, fires a bullet three times heavier than that of the .223 with roughly twice the energy. Previous U.S. military weapons that have fired this cartridge include the M-14 rifle and M-60 machine gun. Now Bushmaster, one of the top manufacturers of .223 semi-auto rifles, is producing a .308 based on the ever-familiar AR-15 platform.
Familiar But Different
Outwardly, the new .308 Bushmaster AR-15 looks very much like any of the company's .223 guns, except that the receiver looks stretched to accept a larger magazine. Bushmaster designed its .308 rifles to use FN FAL magazines that hold 20 rounds.
This decision to use a proven magazine that exists in tremendous quantities was a smart marketing move. Other manufacturers of AR-style .308 rifles either use expensive proprietary magazines or require modifications to existing magazines. That adds substantial extra costs. In contrast, the FAL magazines used by the Bushmaster .308 models can be found at just about any gun show, usually for less than $10 each. Both inch and millimeter magazines can be used without modification.
As it does with its .223 guns, Bushmaster machines both the upper and lower receiver from 7075T6 aircraft grade aluminum and then hardcoat anodizes the receivers. Steel parts are coated with a tough manganese phosphate for corrosion resistance. The result is a beautiful rifle with a nice, even finish that's slate gray in color.
Shooters who are familiar with the AR-15 will find the safety/selector in the same familiar location. But there are some important differences between the .308 Bushmasters and the .223 models. For starters, the .308 Bushmaster has a bolt lock but not in the usual location on the left side of the lower receiver. It's positioned at the junction of the magazine well and the trigger guard and is truly ambidextrous. Inserting an unloaded magazine into the gun and pulling back on the charging handle will lock the bolt carrier assembly to the rear. Firing the gun until the magazine is empty will also lock the bolt open.
In use, I found that I could activate the bolt lock with my trigger finger and actually found it more convenient. Likewise the magazine release is in its normal location but also has an ambidextrous button on the left side of the lower receiver.
The Test Gun
Bushmaster sent me an A2 carbine, which features an integral carry handle sight that is adjustable for both windage and elevation. My test gun had a 16-inch barrel with a 1:10-inch twist, which should stabilize any of the popular projectiles loaded in the .308.
The barrel's muzzle is threaded and has Bushmaster's proprietary Izzy compensator screwed in place. Machined from 4140 steel, the muzzle brake has four gas ports to help fight muzzle rise and is ribbed to help promote cooling. It's one of the nicest compensators I've seen, and I'm certain that it is partially responsible for the carbine's excellent accuracy.
My test carbine was fitted with a skeleton stock. It features an open cell foam cover that surrounds the buffer tube and a rubber butt pad. This stock shaves about a half pound off the total weight of the weapon compared with the traditional plastic shell stock and it is about 3⁄8 inches shorter for quicker handling. There are numerous positions on the stock where you can attach a sling swivel for just about any imaginable style of sling carry. And, if you need the stock to be shorter, removing the rubber butt pad will reduce the length of pull by about a half inch. It's a neat system and my own .223 competition rifle wears the same stock.
Bushmaster includes a forward assist on its .308 rifle. I am dubious about the effectiveness of this addition. Most of the manufacturers of AR-style .308s have chosen to leave this feature off of their rifles. Even Eugene Stoner, designer of the AR-10 and AR-15, resisted when the Army asked him to include the forward assist during the rifle's development.