Safety rules

• Treat every firearm as if it is loaded.
• Never point the muzzle at anything you are not willing to destroy.
• Keep your finger off the trigger until your sights are on the target and you have decided to fire.
• Be sure of your target and what is beyond it.
• Before any disassembly: remove the magazine or empty the cylinder/tube, lock the action open, and physically and visually verify the chamber is empty.
• Remove all live ammunition from the work area before you begin.
• Wear eye protection. Spring-loaded parts can and do launch.

Verifying a firearm is unloaded

Every entry in this database begins with a "Clear and Make Safe" procedure specific to that firearm, because how you verify an empty chamber differs between a striker-fired pistol, a revolver, a tube-magazine shotgun, and a fixed-magazine rifle. Follow the one on the entry page, not a generic version.

Two checks, every time: look into the chamber with good light, and physically feel it with a finger. Brass in a dim chamber can look like an empty chamber. A magazine removed is not a chamber cleared.

Designs that require pressing the trigger

Several common pistols — Glocks, most Smith & Wesson M&P models, and others — require a trigger press to field strip. This is the single most common cause of negligent discharges during cleaning. Entries for those firearms are flagged prominently. Where a design offers a way to avoid the trigger press, such as the M&P's sear deactivation lever, this database documents that method first.

Springs

Recoil springs, magazine springs, firing pin springs, and buffer springs all store energy. Entries list what is under tension on each firearm. Wear eye protection, and disassemble spring-loaded assemblies inside a clear bag or over a contained surface so a launched part is recoverable.

When to stop and see a gunsmith

• Any procedure marked "gunsmith recommended" on an entry page.
• Any time a reassembled firearm fails its function check.
• Any work involving the sear, hammer hooks, trigger engagement, or anything that affects whether the firearm can fire more than once per trigger press.
• Any work affecting headspace, or any firearm of unknown history before its first firing.
• Any time a part does not go together and you are tempted to force it.