What are the reasons for “slam-fires”, and how can they be prevented?
There are four main causes of “slam-fires”: 1. One reason SKS is susceptible to “slam-fires” because of the design of the bolt. They generally use a free-floating firing pin. When the bolt closes on a new round, the firing pin free-floats inside the bolt and forward inertia causes it to contact the primer. The firing pin usually leaves a small indentation on the primer just from the bolt closing. This is normal. Because of this, you need to ensure you are using “mil-spec” ammunition in your SKS. Some US-Made 7.62×39 ammunition uses very soft primers that may detonate just from the firing pin’s inertial contact. Hence, just closing the bolt could fire the weapon—since it’s a semi-automatic, it would automatically cycle the rifle, chamber a new round, and potentially set that one off as well. This typically causes “doubles” or “triples” when closing the bolt. However, it could repeat until the magazine is empty. Other rifles such as the M-14 and M-1 Garand also use free-floating firing p
