Eugene Stoner is perhaps the father of the American .308 battle rifle. While semi-automatic rifles – and even .308-caliber semi-automatic rifles – existed before he introduced the AR-10, few are as innovative as Stoner’s design. Before the M16 series of rifles existed, Stoner designed what looks like an M16 – except in .308 caliber. It was called the AR-10, with the AR standing for Armalite Corporation (who he worked for at the time). It was an instant hit with the military, which had the design scaled down to a 5.56mm round, creating the M16.
The original AR-10 did not die, however – it just never took off like it could have. In a world filled with FN FALs and Heckler and Koch 91s, the AR-10 was seen initially as too expensive and not in as wide a circulation as its competition. While the M16 was being produced in record numbers, the .308 version of the design languished for several decades.
The buzzword for most of Stoner’s designs, including the AR-10, is direct impingement. This term refers to the rifle’s operating system, and while Stoner could not claim to have invented direct impingement, he most certainly refined it and did more with this operating system than any other weapons designer in history. To understand what direct impingement is, consider that the AR-pattern rifles (all of them) are gas operated. What this means is that every time a round is fired, hot gasses from the deflagration of the powder inside the cartridge are harnessed. These gasses mostly exit through the barrel, but some of them are harnessed into a gas tube, and this gas pushes the bolt backwards. The buffer spring pushes the bolt back into battery, stripping off a new round from the magazine, and the process repeats itself. While this procedure is not in and of itself remarkable, what is remarkable is that Stoner’s AR-10 did it without a gas piston. What this means is that the hot gasses directly impinge (push) against the bolt carrier itself, which causes the bolt to unlock and slide rearwards. No piston required.
What does all this mumbo jumbo mean? No gas piston equals less reciprocating mass, which equals greater accuracy with less felt recoil to the shooter. An AR-10 provides a painless and reliable shooting experience to the shooter while saving weight over its competition. The brilliance of this design cannot be overstated.
Resurgence of the AR-10
For decades, the Army’s go-to weapon for sniping and designated marksmanship was the M24 series of sniper rifles. These were based on commercially available Remington 700 series rifles, which were heavily reworked by Army gunsmiths to meet military specifications. While chambering the same round as the AR-10 (.308), they carried only three or four rounds, depending on the model. This presented several problems:
- Designated marksmen and snipers needed to be deployed with security to protect them, since they had no method to quickly return fire if they were overrun.
- If a designated marksman found himself too close to his enemy, or if he was overrun, he would only have his slow-firing bolt-action rifle to fall back on defensively, as well as a pistol in some cases. In either case, he was slow to return fire and under gunned.
- If he wanted an effective security weapon, he would have to lug around an M16 as well, simply for personal protection.
The AR-10 mostly fixed that in what would become the SR-25. Created by Stoner while he worked at Knight’s Armament, the SR-25 was the Army’s answer to the problem. The SR-25 is essentially a .308 AR with a silencer, featuring a twenty-round box magazine. The shooter could now engage multiple targets without ever having to remove his cheek weld to work the bolt. If he was overrun or had to use the rifle defensively, he could simply pick it up, fire from the hip or shoulder, and shoot back semi-automatically, just about as fast as an M16. The SR-25 is amazingly accurate as well, more or less as accurate as the bolt-action M24 the army previously used.
You can build or buy an AR-10 type rifle that will have the identical capabilities to the SR-25 just about anywhere in America. The only thing missing would be the silencer, and you can even get that in some states. While .308 AR parts are generally more expensive than 5.56 AR parts – about double – you wind up with an extremely capable rifle that can shoot single ragged hole groups at 500 yards and effortlessly reach out to 1,000 yards with the right optics. And all this with a twenty-round box magazine that changes out in seconds. You can hold a lot of people at bay at very, very great distances with this rifle. Eugene Stoner invented this rifle in the late 1950s, and it’s still going strong today. In fact, it’s in its prime!