Even with meticulous preventative maintenance and the use of quality fasteners and proper tooling, precision rifle builders and enthusiasts will inevitably encounter damaged screws. Whether a screw head is stripped or a shank has sheared off flush with the action, these situations can halt progress on a build or during routine maintenance. Fortunately, established methods exist for tackling these common issues.
For a stripped screw where a wrench or driver can no longer engage the head, a common initial attempt involves tapping a larger Torx or Allen style bit into the damaged head to gain purchase. When this proves insufficient, a more direct approach is often necessary: drilling out the screw head. This involves selecting a drill bit slightly larger in diameter than the screw's shank. With the rifle action securely held in a vise, the head is carefully drilled away, allowing it to separate from the shank. The remaining threaded shank can then typically be gripped and backed out using a set of locking pliers, a method often cited for its effectiveness over many years of application.
Sheared screws, particularly those broken off flush with the action surface, present a more intricate challenge. Unlike a stripped head, there's no material to grip, and attempts to cut a slot for a screwdriver are rarely successful if the break is perfectly flush. In such cases, drilling out the entire screw is usually required. While some practitioners may attempt this with a handheld drill, the preferred and recommended method involves securing the action in a v-block on a milling machine or a high-quality drill press. The process begins with a spotting drill to precisely center the hole, followed by an undersized drill bit. The screw is then incrementally drilled out using progressively larger bits. If the drilling remains perfectly centered, the screw material is removed cleanly. Should the drill drift off-center, a small punch can often be used to collapse and remove the remaining screw fragment.
In some instances, after drilling, a tap may be necessary to clean or re-cut the threads in the action. While encountering damaged screws can be frustrating and time-consuming, these issues are generally resolvable. It is frequently advised that such modifications or repairs be undertaken only by competent or licensed gunsmiths, as improper procedures can lead to an unsafe firearm, void warranties, and potentially result in injury or death.
