AR-15 Rifles

AR-15 is a frivolous, semi-automatic, center fired rifle. It is operated using gas and is not heavy to carry and operate.
The design of the AR-15 rifles is based on the 7.62mm AR-10 rifles. The credit for the design of these light weight rifles goes to Eugene Stoner of Fairchild ArmaLite Corporation. AR as in the name suggests ArmaLite.
AR-10 rifles are just 5.62mm version of the AR-10 rifles.

History of AR-15 Rifles
Way back in 1959, the rights related to this series of guns were sold to Cold by ArmaLite. ArmaLite marketed this series of guns exclusively to several military services across the world. US military service started using this series of guns under the code M16.

Operating Mechanism of AR-15 Rifles
AR-15 Rifles work based on the direct gas impingement mechanism
High Pressure acts on the firearm's path directly thereby reducing the conventional cylinder, piston and rods. This in turn saves design cost and weight of the rifle.
In this case of AR-15 rifles, the rear side of the firearm from here the ammunition is loaded gets spoiled more quickly due to the deposits that emerge out of cooling mechanism.
Yet another problem with these rifles is the fact that the bolt carrier and the bolt that get in touch with the combustion gases tend to get overheated instantly.

The Design of AR-15 Rifles
Designing and operating an AR15 is simple. The main accessories that are needed for building the AR-15 rifles are a torque and a barrel nut/free float tube wrench, a barrel/action, a pair of nose pliers, a screw driver, a hammer, an X-Acto knife and a center punch. These items are readily available with any retailer who is into selling AR-15 parts.

Design Issues
Chamber pressure is usually much higher in case of AR-15 rifles. Usually this is very much more than what the barrels used can tolerate. This proves to be a major design concern associated with AR-15 rifles. Wylde chamber is the alternative design used by several manufacturers that enable them to overcome this issue associated with chamber pressure in AR-15 rifles. Yet another design concern is the manufacture of the firing pin. Manufacturers often make it sturdy and tolerant so as to avoid the occurrences of slam fire during the process of loading these rifles.

Features of AR-15 Rifles

Originally designed and marketed by ArmaLite, these guns have the following unique features:

• The unique design gives provision for a number of accessories.
• Repairing a AR-15 rifle is easy
• AR-15 rifles have a sturdy aluminum receiver
• Gas impinging mechanism used is direct and unique
• Front and rear side adjustable elevations is remarkable benefit with AR-15 rifles

As per the Assault Weapons Act, the use of certain variants of AR-15 rifles were banned in the United States of America from 1994-2004. However, if an upper receiver is attached to the lower receiver of AR-15 which can be legally used in USA, then this arrangement renders the use of AR-15 legal.