Dry fire

Dry firing is the practice of "firing" a firearm without ammunition. That is, to pull the trigger and allow the hammer or striker to drop on an empty chamber. Dry firing may be mechanically damaging to some firearms – especially rimfire weapons, where the firing pin in most designs will impact the breech face if the weapon is dry-fired. Because of this, precautions (such as the use of snap caps) need to be taken if such a weapon is to be deliberately dry-fired.

This technique is often used to simulate actual firing when there is not a suitable place to practice with live ammunition. The primary benefit of this practice is refined trigger control. For most common cartridges, there are snap caps available to reduce the risk of damaging the firing pin. The technique allows people to conduct a safe, economical form of training to improve their shooting skills. An emphasis is placed on safety to prevent an accidental discharge. Training should be conducted in an area with no ammunition and with a suitable backstop.

In recent years, a number of companies have developed methods of enhancing dry fire practice to improve skills. Products that fire a laser, as opposed to a solid projectile, have become increasingly popular. These include chamber inserts available for various caliber firearms, as well as dedicated training pistols or replacement AR-15 bolt carrier groups. There are also a number of target systems for these laser dry fire training aides, that are becoming more affordable and popular. These products help people get more from dry fire practice by providing feedback on shot placement and times, and make dry fire a more enjoyable experience.

It is generally acceptable to dry fire more modern centerfire firearms without a cartridge or snap cap. Older designs such as the CZ 52 and Colt Single Action Army are exceptions. However, dry firing a rimfire firearm or guns with angled firing pins (such as revolvers with hammer-mounted firing pins or older shotguns) can damage the gun. Furthermore, damage can occur to the chamber mouth of a rimfire firearm. Ultimately, one should check with the manufacturer of the gun to ascertain if it is safe to dry fire.

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Wikipedia