XIII. Safety and Security

A. Safe Use of Firearms

0. Gun Safety

c. Common Causes of Accidental Discharge and Failure to Fire

by John Gilman (jgilman@hpcvsgen.cv.hp.com)

Accidental Discharge:

Some eighty-five percent of all accidental discharges (AD's) are the result of the deliberately pulling the trigger on an "empty" gun. Avoid this by minimizing dry firing, by keeping ammunition in a separate room, and by double checking for cartridges in both the chamber and the magazine of repeating arms. Especially don't look down the barrel of a firearm whose action is closed!

Perhaps seven percent are due to the trigger finger being forced inside the trigger guard whilst holstering a handgun or boxing a rifle. Avoid this by never holstering a loaded firearm, or if you do, keep your trigger finger extended at a sharp angle to the trigger guard.

About four percent are due to lousy trigger job/worn trigger and sear. Avoid this by doing trigger work yourself, or having some trusted individual look over the hammer/sear interface once every few thousand rounds.

About two percent are due to a defective safety. Avoid this by not trusting the safety.

Of the remainder, most are due to a foreign object being forced inside the trigger guard. This is especially true of hunting rifles and shotguns. Avoid this by keeping your trigger finger as a shield over the trigger guard, whilst carrying afield.

Keep in mind that if you shoot long and often enough, you too, will have an AD to your credit. Hence, it is really important to always control the muzzle of your firearm. When the round goes downrange, it sure as heck better end up in a concrete wall, earth berm, or tree trunk.

Failure to Fire:

Probably eighty percent of all failures to fire, are because the firearm's chamber was empty. Often, it is because someone else has handled the gun, and made it safe. Sometimes, it is because the bolt/slide did not retract far enough to pick up a new round from the magazine (often called short-stroking). Also, the shooter may have become confused, and dropped the slide/closed the bolt prior to inserting a fresh magazine. Avoid all these things by doing what is called a "press check" prior to using the firearm. Perform a press check by withdrawing the bolt/slide far enough to see into the chamber - but NOT far enough to introduce a new cartridge to it! Typically, a press check will leave the firearm cocked - so afterwards you will probably need to point the gun at the ground and pull the trigger, or simply uncock it.

About ten percent are due to light firing pin hits. These are usually in turn brought on by a poor trigger job or fatigue of the hammer spring. On rare occasion, ammunition may have hard primers, quite resistant to impact. Avoid this by quality trigger jobs, replacing hammer springs occasionally, and using brand-name ammunition.

Perhaps five percent are due to improperly seated primers. These drive forward when struck, absorbing hammer energy that should have gone into dimpling the primer. This is fairly common in handloaded ammo, but rare in factory stuff. Avoid the problem primarily by using factory ammo, and by inspecting it while loading.

Perhaps three percent are due to defective primers that either don't have priming compound, or whose anvils are defective, or that have been contaminated with oil. You will have a devil of a time avoiding this.

Perhaps two percent are due to a number of remaining causes. The firing pin is broken, or the gun wasn't in battery, or there is binding in the trigger/hammer mechanism. Avoid/minimize by frequent firearm inspection.

Effects of the above may be minimized by practicing clearance drills for each occurrence, for your particular firearm.