Anyone familiar with AR15 builds will know that there are a whole bunch of advanced, specialized coatings applied to bolt carrier groups that offer superior permanent dry lubricity, as well as excellent resistance to wear and corrosion.
But what about other parts, like stocks, handguards, pistol grips, and accessories? These are not made from the same material as the bolt carrier group (which is made from steel). Many AR15 parts, like the receivers, grips, and handguards, are made from aluminum instead.
This is an entirely different material, and one to which different treatments can be applied. The prevalence of aluminum (the virtues of which will be explored below) means that the same coatings are not applicable.
One common process - known as anodization - which results in AR15 anodized parts, is. This post will take a closer look into this process, what it means for treated parts, and what the selling points of AR15 anodized parts are.
What Is Anodization?
Anodization, also known as anodizing, is an electrochemical process whereby the surface of a metal alloy is converted into an anodic oxide, which is a very hard, corrosion and wear-resistant finish that cannot be wiped or easily worn off.
Anodization can be applied to a variety of nonferrous metals, commonly aluminum, although magnesium and titanium can be anodized as well.
When the alloy affected is aluminum, the process converts the surface of the alloy into aluminum oxide, which, though it is porous, is fully integrated with the underlying aluminum substrate. As a result, it cannot chip off or be removed mechanically, except by fully abrading the anodized layer.
To achieve this finish, the aluminum workpiece is typically submerged in an acid electrolyte bath and electrified. A cathode placed inside the bath forces the aluminum workpiece to function as an anode, and as oxygen ions are released from the bath, they cleave to the aluminum at the surface of the workpiece.
This process leaves a residual layer of aluminum oxide on the surface of the workpiece, which can then be colored or further sealed.
Now that we can see that anodized aluminum is basically aluminum that has been oxidized under controlled conditions, we can take a closer look at why it is so common to apply this process to parts that are commonly used on AR15 rifles and other firearm platforms.
Why AR15 Anodized Parts?
There are numerous selling points for AR15 anodized parts, that put them on the same field as Cerakoted parts, or alternatively, steel parts that have been nitrided or finished with a DLC coating.
The first reason that AR15 anodized parts are attractive to tinkerers, hobbyists, and other home-builders is mechanical. The aluminum oxide surface layer is extremely hard and wear resistant, and it is very hard to scratch or mar it. For what it’s worth, the finish is also non-toxic.
Oxidizing the surface layer of the aluminum also “pre-corrodes” it, for lack of a better term, making the resultant anodized piece effectively corrosion resistant from that point on. Not that aluminum is heavily affected by oxidative stress, but it is still something to consider.
It follows that AR15 anodized parts are therefore chemically stable and the finish will not degrade or decompose under normal circumstances. In fact, an anodized finish is thermally stable up to the melting point of aluminum, which is over 1000℉. If it’s so hot the anodized finish is in jeopardy you have bigger problems.
Anodized aluminum is also available in a wide range of attractive, bright, metallic colors, which some builders and tinkerers appreciate because it makes color-customization of a rifle easy and affordable. That’s another thing - AR15 anodized parts are not prohibitively expensive.
Finally - and though this is not a big concern with most parts that are commonly anodized - like many steel finishes commonly used in firearms manufacturing, anodized aluminum offers decent permanent dry lubricity, so moving parts with it are better served.
Why Aluminum?
Last but not least, let’s take a look at why so many parts of an AR15 are made of aluminum and not steel (which is the case with many other firearms platforms).
The weight of an AR15 with a loaded mag is around 6.5 pounds, although that figure will vary according to barrel length, handguard type, and what attachments are present. It’s a good estimate, though.
If the rifle were made with all steel components instead of aluminum, say, for the stock, receivers, handguard, grip, and other parts, it would weigh substantially more - perhaps even several times more.
So, in a nutshell, aluminum parts are better for some rifle components simply because aluminum is functionally very strong but several times lighter than steel. Anodized or not, aluminum makes sense.
Shop AR15 Anodized Parts Here
In the market for some upgrades? Shop our full collection of AR15 anodized parts here and get in touch with us at Sales@MCSGearup.com if you have any questions before buying.