Are Guns Made of Iron?

Firearms have been made of various materials over the ages. Modern firearms, while functionally the same as their predecessors, use a variety of modern materials. In this article, we will discuss these various materials and their uses.

Are guns made of Iron?

Most firearms today are made of steel and thus have iron in them. Advances in metallurgy have moved us away from the large and heavy firearms of the past, but even modern steels used in modern firearm manufacturing are still primarily made of iron.

Understanding that modern firearms are frequently a combination of materials, lets dive into what one can expect from a modern firearm in terms of what materials they are made of, as well as where one might expect to see these materials used. Additionally, we will see where iron is still used in modern firearms and why the metals of early firearms production were abandoned in favor of modern steel.

Iron is great, but steel is better.

Iron is an elemental metal. It can be found on and in the earth, and has been used for centuries. Iron has many uses, due to its high strength and durability compared to many other materials. However, iron by itself in its most basic manufactured forms is generally very heavy. While stronger than wood or other materials, pure smelted iron or even early iron alloys were still weak compared to their modern counterparts. A look at early firearms and cannons exhibits the limitations of iron. Even small arms and cannons were large and heavy as the thickness of iron required to safely contain the pressure of even early black powder required increasingly thick chambers. Overbuilding these early firearms also allowed for a margin of safety as precision in loading was not always possible.

As metallurgy advanced through the ages it was discovered that if you added additional elements to iron you could increase the strength of the resulting material while simultaneously reducing weight. When carbon is added to iron in even small amounts 1-5% it drastically changes the resulting metal. Carbon allows the iron to become hard and less ductile than when in its pure form. This change also increases the strength of the alloy allowing a thinner material to be used in the same place as a thick heavy iron. When carbon and other elements are added to iron we call the resulting material steel.

The invention of steel arguably changed the firearm into a much more efficient and effective weapon and tool. Steel allowed firearms to become lighter, allowing the soldier or hunter to be more mobile. Steel also allowed the pressures of the combustion chambers to be higher, which allowed increased velocities and effective ranges of firearms.

Where is iron used in firearms today?

Barrels, frames, sights, cylinders, triggers, scope mounts and rings are a few places that you might commonly find steel parts on a modern firearm. Some of these parts may be made from other non-ferrous metals (non-ferrous – metals without iron), however with the exception of a few novel firearms the barrel is almost always going to be made of steel.

Steel is a superior metal for barrel making because it has all the desirable properties one would want for a barrel. Machineability, strength, and the ability to be hardened. Barrel makers can use a variety of steel alloys, but 4140/4150 carbon steel alloys and 416 Stainless or similar steels are very common.

Rifle bolts, pistol slides, and frames are also places where steel is the primary choice of material. For the same reasons that steel is great for barrels, steel is great for these other parts of the firearm. Like barrels, manufactures can use a different alloy of steel selected based on the expected use or for the specific aesthetic of the firearm.

While this is not an exhaustive list of everywhere steel is used in modern firearm making, it can be noted that steel is often the material of choice for any part of the firearm that requires high durability or strength.

What other materials are used today?

Metal framed pistols are frequently comprised of various steel alloys, however other modern metals are used when a lighter weight is desired. Scandium and aluminum alloys are frequently used in revolvers, and of course AR-15 pattern firearms are almost always made from aluminum for the upper and lower receivers.

As mentioned aluminum is another very popular metal used in modern firearms production. Aluminum offers high strength with incredibly lightweight. It is popular as a frame or receiver material as well as for handguards on AR-15 style rifles. Aluminum is the standard for most modern riflescopes from low end to high-end. Aluminum is also a popular choice of material for scope rings and scope mounts when weight is a consideration. Steel is also used for these items when extreme durability is required.

Even with the increasing adoption of carbon fiber barrels, there is still steel involved. Carbon fiber barrels consist of a rifled steel barrel sleeve wrapped in carbon fiber. Carbon fiber provides an extremely rigid barrel that is also significantly lighter than steel.

Wood and wood-based materials are still common materials found in modern firearm manufacturing. Laminate wood and solid wood stocks are still widely used and offer a rigid platform on which to build a firearm, and with modern advancements in manufacturing and production are better than ever.

While wood is still used in modern firearms, polymer and composites have become a common material for many gun stocks. Synthetic material stocks are extremely common for both rifles and shotguns. Modern synthetic materials are generally impervious to most environmental stressors in normal conditions and exceptional at resisting warping from wet or humid environments which sometimes can negatively effect wood stocks.

Polymer and composites are not limited to only stocks. Polymer framed pistols have in many ways become the standard for modern semi-automatic pistols. However is should be noted that even these modern polymer pistols still have some steel parts and sometimes even steel frames embedded in the polymer frame.

What material is best?

With so many metals and other modern materials being used in modern rifles, pistols, and shotguns, is there one material that is best? The answer to that is no, generally, every material has its place. As mentioned above, when it comes to barrels, there is going to be steel involved. Are there other metals that could be used, yes, but generally the high availability and relatively low cost of steel will continue to make it the material of choice.

Firearms have been around for centuries and will continue to remain for centuries. What will these future weapons look like is anyone’s guess, but chances are, they might in some part be made of iron.

Polymer Frame (Top) Steel Frame (Middle) Aluminum Alloy (Bottom)