A gunsmith screwdriver is a tool used in the assembly and disassembly of firearms. Created with a hollow-ground tip, the gunsmith screwdriver differs from the basic household screwdriver in that the basic screwdriver tip is taper-ground. The steel used in the manufacture of a gunsmith screwdriver is very hard, therefore, the screwdriver is able to apply excessive torque without damaging the screw or bolt head. Commonly purchased in kits containing several of the most common types and sizes of screwdrivers, the gunsmith tools are typically more expensive than regular home workshop types of screwdrivers.
The fasteners used in the production of firearms have unique head designs. Unlike the common house screw, the slot in firearm screws is very deep to allow proper torque to be applied when assembling or breaking the weapon down. This type of fastener requires a special tool so that the slotted head does not become damaged from the tool slipping out of the slot. The gunsmith screwdriver uses a hollow-ground tip that is the same size for a good deal of the screwdriver blade, instead of using the taper-ground tip found on the typical household tool. The taper-ground tip begins to taper outward from the tip — directly after the tip —, creating a tool that will not fill the screw's slot on a firearm screw.
By using only a gunsmith screwdriver when working on a firearm, the screw slot is properly filled. This also allows the gunsmith screwdriver to be used to apply excessive force and torque without damaging or marring the head of the screw. For the best results, the correct-sized gunsmith screwdriver should be used for every application. Should the exact size required not be contained in the screwdriver kit, the next closest smaller-sized screwdriver will usually produce satisfactory results. It is also important to use the special gunsmithing tools when mounting a scope or other types of optics to avoid damaging the mounting screw heads.
The problem with using an ordinary screwdriver straight out of the tool box to work on a firearm is that the heads on the firearm screws will typically become damaged. This damage is caused from the tapered screwdriver tip riding up and out of the firearms fastener, tearing the crisp edges out of the screw and leaving the heads peeled back and damaged. The type of damage associated with the omission of a gunsmith screwdriver not only decreases the value of a firearm — it could impair the weapon's functionality by causing jamming, misfiring and sticking.