The worlds most popular sporting rifle today is the AR-15. This platform is the most versatile weapons system ever created. Designed by firearms legend Eugene Stoner in 1959 to be the rifle to replace all rifles. Little did Mr. Stoner know what his design would bring to the world. Originally designed in 5.56x45mm (Military designated .223 cartridge) the round is capable of effectively dispatching any combatant up to a range of 660 meters. Because of the effectiveness of this rifle Mr. Stoner sold the idea to the Colt Manufacturing Company in 1959 shortly after he designed it. Everything following that is history.
The AR-15 was dropped straight into combat during the Vietnam war designated as the M16a1 service rifle. First run weapons had many issues because of the weapons operating mechanism. the mechanism would jam from all the mud and grime from ground combat in Vietnam. Another contributing factor is the powder used in the ammunition produced. Companies used cheap “ball” powder instead of the better and more efficiently burning stick powder used in todays applications. The main mechanism of operation for the rifle is known as direct gas impingement. Impingement firearms work from using gas used from a fired projectile.
The AR-15 was dropped straight into combat during the Vietnam war designated as the M16a1 service rifle. First run weapons had many issues because of the weapons operating mechanism. the mechanism would jam from all the mud and grime from ground combat in Vietnam. Another contributing factor is the powder used in the ammunition produced. Companies used cheap “ball” powder instead of the better and more efficiently burning stick powder used in todays applications. The main mechanism of operation for the rifle is known as direct gas impingement. Impingement firearms work from using gas used from a fired projectile.
“Gas is tapped from the barrel as the bullet moves past a gas port located above the rifle's front sight base. The gas rushes into the port and down a gas tube, located above the barrel, which runs from the front sight base into the AR-15's upper receiver. The bolt and bolt carrier together form a piston, which is caused to expand as the cavity in the bolt carrier fills with high pressure gas. The bolt is locked into the barrel extension, so this expansion forces the bolt carrier backward a short distance in line with the stock of the rifle to first unlock the bolt. As the bolt carrier moves toward the butt of the gun, the bolt cam pin, riding in a slot on the bolt carrier, forces the bolt to turn and unlock from the barrel extension. (The gas system only serves to unlock the bolt once the projectile has exited the barrel). Once the bolt is fully unlocked it begins its rearward movement along with the bolt carrier. The bolt's rearward motion extracts the empty cartridge case from the chamber, and as soon as the neck of the case clears the barrel extension, the bolt's spring-loaded ejector forces it out the ejection port in the side of the upper receiver. The bolt is much heavier than the projectile, and along with the recoil-spring pressure inside the stock buffer-tube performs the cartridge ejection function and chambers the following cartridge. Behind the bolt carrier is a plastic or metal buffer which rests in line with a return spring that pushes the bolt carrier back toward the chamber. A groove machined into the upper receiver traps the cam pin and prevents it and the bolt from rotating into a closed position. The bolt's locking lugs then push a fresh round from the magazine which is guided by feed ramps into the chamber. As the bolt's locking lugs move past the barrel extension, the cam pin is allowed to twist into a pocket milled into the upper receiver. This twisting action follows the groove cut into the carrier and forces the bolt to twist and "lock" into the barrel's unique extension.”
The AR-15 is still used by every branch of the United States Military which is currently designated the M16a4 and the M4 carbine variant. The Marine Corps trains with the rifle and produces riflemen accurate and reliable to 660 meters or 721 yards. The rifle has been in service for 49 years. Thats the second longest service history of any U.S used firearm. Over 8 million M16 and its variants have been produced and sold to the United States Armed Forces.
The AR-15 is one the most effective weapons platforms ever created despite early ammunition issues. Our Military is based off the 8 million rifles in service and has defended our troops and nation for 49 years. The lives of hundreds of thousands of servicemembers have been protected by Eugene Stoner's ingenious idea of the direct impingement, lightweight, 5.56mm, air-cooled service rifle.
Source: The AR-15
The AR-15 is still used by every branch of the United States Military which is currently designated the M16a4 and the M4 carbine variant. The Marine Corps trains with the rifle and produces riflemen accurate and reliable to 660 meters or 721 yards. The rifle has been in service for 49 years. Thats the second longest service history of any U.S used firearm. Over 8 million M16 and its variants have been produced and sold to the United States Armed Forces.
The AR-15 is one the most effective weapons platforms ever created despite early ammunition issues. Our Military is based off the 8 million rifles in service and has defended our troops and nation for 49 years. The lives of hundreds of thousands of servicemembers have been protected by Eugene Stoner's ingenious idea of the direct impingement, lightweight, 5.56mm, air-cooled service rifle.
Source: The AR-15