When customizing your AR-15, the type of barrel you select will have a noticeable impact on your shooting experience and the overall quality of your rifle. There are two major categories: chrome-moly steel, with a chrome-lined bore and chamber, or stainless steel. So which type is best suited for your gun?
Well, it depends what kind of shooting you’re doing. But first, a general overview:
4150 Chrome-moly Steel
The most popular kind of barrel material is chrome-moly steel, specifically 4150 chrome-moly steel. This is what is typically found in mil-spec firearms. There are only slight differences between the 4150 and the 4140 forms, and while the 4150 is the standard for the U.S. military, the 4140 may do for the average civilian shooter. Chrome-moly steel is strong, hard, and highly durable. It requires heat treatments (which harden the steel so it can withstand the pressure of use) to avoid rusting and maintain accuracy, but if properly treated, chrome-moly steel has a long lifespan.
One of the important factors when selecting a barrel is whether or not it’s chrome lined. Chrome lined barrels have a layer of slick, hard chrome on the inside bore. While it extends the life of the barrel, is easier to clean, and is more corrosion resistant, long-range accuracy is affected by the fact that chrome lined barrels are slightly uneven. Another factor to consider is whether your barrel is rifled or not—this means that it has spiral grooves cut into the bore that cause the bullet to rotate and stabilize. Chrome lining protects the rifling of the barrel.
416 Stainless Steel
Stainless steel barrels, specifically 416 stainless steel or “match grade” barrels, are more expensive, but that’s an indication of the quality. This type of stainless steel isn’t like the one in your kitchen appliances; it’s made with high amounts of chrome and sulfur in the steel, which makes it able to be manufactured with great precision to be rust resistant. 416 stainless steel has the ability to burnish so it is easier to clean. They typically are not chrome-lined, which contributes to their superior accuracy.
If you’re looking for medium range target shooting, or for defense purposes, chrome-moly steel will certainly serve your purposes. But if you want to be able to maintain accuracy over time, perhaps for competition purposes, stainless steel is the clear winner.
416 stainless steel is also the one that is optimal for performance alongside the DigiTrigger— because we are all about increasing accuracy, having a barrel that also increases accuracy in addition to the DigiTrigger will greatly enhance your ability to hit your target, every time.