Here at Cheaper Than Dirt!, we get many questions about milled vs. stamped receivers. Today, we will discuss the differences between the two and explain how to identify different AKs.
AK-type rifles have two main types of receivers: milled and stamped. These days, the country of origin is usually the determining factor in which type you may possess. Distinguishing the two can be a task for someone who does not know the specific differences. The following tips should help you learn those differences so you can identify your type of receiver.
The first AK-47s had milled receivers. Manufacturers machined each from a solid block of steel, which made them very sturdy but also very heavy. One of the easiest ways to visually differentiate a milled receiver is the large, rectangular-shaped cutout, which is nearly 5 inches long, above and in front of the magazine well. It was designed to reduce the overall weight of the rifle.
The trigger guard is stamped and riveted on to the bottom of the receiver in a similar way as a stamped receiver. The pistol grip nut is riveted in place on the receiver just behind the trigger guard. The magazine well and magazine front latch slot are machined into the receiver. You should also notice that some of the sharp edges above the trigger and magazine were milled off (chamfered).
Stamped receivers are more common and easier to build or make yourself. While makers machine milled receivers out of solid blocks of steel, they “stamp” stamped receivers from a flat piece of thin metal bent into a box shape and riveted with a center spacer with both front and rear trunnions. Visually, you can easily differentiate stamped receivers from milled ones by noticing the small, shallow indentation—about 1-inch long—on each side of the receiver, directly above the magazine well. The indentation is called the “magazine guide,” which should not be confused with the large, weight-reducing cutout found on a milled receiver. You also can differentiate the two by the many external rivet heads on the sides of a stamped receiver.
The trigger guard is stamped, just like milled, and riveted on to the bottom of the receiver. The grip screw nut, however, is a separate piece that fits down from inside the receiver through a square hole behind the trigger guard. Pistol grips usually are interchangeable between receiver types.
Most think milled receivers are stronger than their stamped counterparts. Some authorities also believe they are more inherently accurate, but there are some who dismiss that difference as negligible or deny it altogether. Despite the differing opinions, according to Soviet manuals, stamped receivers generally have a longer life expectancy in terms of rounds fired.
There are many countries making both types of receivers, so please do not assume that your receiver is milled or stamped based on its country of origin.