As a material that is renown for its low density, versatility, and strength, aluminum is critical to a wide swath of industries, from aerospace to food and beverage. Its natural attributes also make aluminum a key material in the manufacture of guns and gun accessories. Because of its lightweight when compared to steel and other alloys, aluminum has become an important material in the gun industry, with many guns made predominately from an aluminum alloy, and even more that rely on aluminum for key parts of the gun, such as the scope, the handguard, or buffer tube.
Why Is Aluminum Good For Guns?
While there are certain specialty guns that are exceptions, when it comes to the manufacture of gun bodies, the choice comes down to two metals, steel or aluminum. While stainless steel alloys tend to be stronger and thus have greater durability over the lifetime of a weapon, aluminum can more than make up for this deficiency due to its lighter weight.
Previous to World War II, aluminum was considered to be quite expensive to work with because of the difficulty in refining the raw ore. Industrial advances during the war period meant that aluminum, one of the most prevalent elements in the Earth’s crust, became cheaper and more versatile, and so it quickly became adopted by many industries that previously avoided its use.
In 1949, Colt debuted the Lightweight Commander, an upgraded version of its Government Model that also happened to be 30% lighter. Because aluminum offered such a great weight reduction, it quickly became adapted in a number of other models as well, to the point that today aluminum is widely recognized by gun owners and manufacturers as a quality choice in handguns and rifles.
Of course, aluminum-framed weapons traditionally aren’t as durable as those made from steel. Aluminum lacks the tensile strength that steel exhibits. Another issue is with the ergonomics of the piece, as the choice of alloy also affects the balance and grip width. Also to be considered, aluminum is less capable of handling an automatic weapon’s slide recoiling into the frame and is less resistant to flame cutting and stretching. But for many users, the lighter weight more than makes up for these issues.
What Aluminum Alloys Are Used In Guns?
When it comes to alloys, guns generally use one of two types, 7075 or 6061.
6061 aluminum alloy is better known as aircraft aluminum. It is composed of trace amounts of silicon, copper, manganese, molybdenum, and zinc. It was first manufactured in 1935 and because of its light weight and ease of fabrication into complex parts, it became extremely popular with aircraft manufacturers.
A much stronger choice is 7075 aluminum. It is made up of more significant amounts of copper, manganese, chromium, and zinc, and therefore has more corrosion resistance. Early guns that used 6061 had difficulty dealing with wet environments and even human sweat, which were major problems in the jungle environments of Southeast Asia.
No matter what alloy you use, aluminum is too soft on the surface and must be hardened by anodizing it. This process involves dipping the aluminum into an acidic solution while at the same time conducting electricity through it. The natural oxidization hardens the surface and it then must be treated with a sealant.
Examples Of Aluminum Guns
There are any number of guns being manufactured today that use aluminum alloys in them, including some of the most popular guns in history. The M-16’s receiver is made with 7075 aluminum, as is the frame of the Beretta Model 92, one of the longest serving models in American history. One example from the 1950’s highlights why aluminum became a popular choice in firearms.
The Colt Aircrewman was used by the United States Air Force beginning in 1950. Because every ounce needed to be accounted for when flying, it was imperative that the lightest weight material be used whenever possible. Pilots faced the very real possibility of being shot down during combat, and so they wanted to carry a pistol with them just in case. Colt began manufacturing the .38 caliber Cobra with aluminum frames and cylinders and renamed it the Aircrewman to serve this purpose.
The ultra-lightweight handgun weighed only 11 ounces when fully loaded and thus could be safely carried on board during flights without adding too much weight. In the end, because the Aircrewman required special ammunition that made it impractical (and quite dangerous if loaded with normal rounds), they stopped manufacturing the gun in the 1950’s. The latest developments in the use of aluminum meant that newer guns could use regular rounds yet still be lightweight and durable.
Today, many classic models are being updated with aluminum frames. For example, the UA Arms Integrated Aluminum 1911 is made of a composite aluminum pistol body that is up to 60% lighter than steel alternatives, yet it still claims to have the same level of durability.
A favorite among law enforcement agencies, the 1911 has utilized the same basic design since it’s inception. And while it was known to be remarkably durable, it also happened to be quite heavy. Although it was already popular among concealed carry permit holders, a significant weight reduction would make the 1911 even more practical and popular.
UA Arms uses an explosive metal welding technique to produce materials combining different metal types in a single work piece, thereby retaining the best qualities of different types of metal, allowing for reduced weight, increased thermal conductivity, and greater strength and corrosive resistance. The explosive welding technique bonds the metals at the molecular level.
Summary
It is these kinds of advances in the gun industry that are making aluminum such a popular choice among firearm enthusiasts. When you can increase its durability while retaining its lightweight qualities, there is no end to the versatility of aluminum. Its high quality, strength, and flexibility also mean that aluminum is more cost effective than most other materials.
Sources:
http://www.chuckhawks.com/pistol_construction_materials.htm
http://www.guns.com/2013/02/06/the-colt-aircrewman-special
http://www.uaarms.com/New_Lightweight_1911_Pistol
