#Pins

Strike Industries has introduced new AR-15 takedown and pivot pins called Shift Pins. Besides the nice look of the pinheads, the Shift Pins also feature a special pattern of grooves that allow installing and removing these pins without a need of tools or need to disassemble other parts like the buffer tube, castle nut, and endplate. The best way to have an idea about how these pins work is to watch the video published by Strike Industries.

Strike Industries’ solution to the problem of rotating and walking out AR-15 pins is pretty unique and simple as in the case of many other of their products. The pins of their anti-walk/anti-rotation system extend a bit over the lower receiver exposing a groove. The retention itself is accomplished by an external clip.

To me, the only major and glaring design issue behind the AR-15 and similar two-receiver designs is the interface between the two receivers. By using only two pins and having variable tolerance between them for mass-manufacturing inevitably leads to excessive slop. This is compounded by the choices in materials as steel rubs on aluminum receivers (but that is another issue entirely).