Firearms safety has been at the forefront of responsible gun ownership since as early as 1860. Back then, the trigger guard emerged as one of the first universally adopted safety features. Over the years, however, the landscape of gun safeties has evolved, ranging from active safeties like levers to passive mechanisms such as firing pin blocks. Let’s delve into the intricate world of gun safeties, breaking down their types and focusing on specific aspects that cater to both beginners and seasoned shooters.

Early Revolver Safety

After the trigger guard came a half-cock notch in the gun lock. Most revolvers were single-action, and the half cock notch caught the hammer if you slipped during the cocking process. That prevented the hammer firing. A special safety cylinder was designed for the Colt 1860 that allowed the hammer to rest between cylinders — one of the first of its kind. And the Starr revolver was factory-equipped with such a device.

For the most part, revolvers were carried with an empty cylinder under the hammer. By the 1880s, a rebound-type hammer was developed. The hammer spring ran the hammer forward to fire the revolver; then the rebound spring moved the hammer away from the cartridge and kept it there. Hammer blocks were universal in quality double-action revolvers by 1900 but lagged behind for many years in single-actions.

Though not altogether nonexistent, manual trigger and hammer-locking safeties were rare on revolvers. The passive safety transfer bar, positioned between the hammer and firing pin, marked a milestone in revolver safety. A passive safety requires no active manipulation. As the trigger is fully pressed, the transfer bar rises. The hammer falls and transfers energy to the transfer bar, and the transfer bar strikes the firing pin. That releases the trigger, and the hammer springs back. This innovation has made modern concealed carry revolvers some of the safest ever manufactured

Revolver design is also responsible for a common feature on single-action self-loading pistols: the grip safety. The grip safety would lock the action until the revolver was firmly grasped and the lever depressed. These were called hammerless revolvers, as the hammer was concealed and could not be cocked for single-action fire.

Safety Devices for Self-Loading Firearms

With the introduction of self-loading pistols came a dizzying number of safety devices. Practically all that are in use today were invented before 1920. The most important early development was the inertia firing pin. Firing pins were once full-length and rested on the primer of a chambered cartridge. Inertia firing pins are shorter than the firing pin channel and do not rest on the primer when the hammer is down. The hammer smacks the firing pin on firing and drives it forward, firing the pistol. The firing pin is then retracted to its original position by the firing pin spring. This isn’t perfect, however. If the gun is dropped on the muzzle, the firing pin may take a run forward and fire the pistol.

There are two means of making the pistol drop-safe and preventing a negligent discharge. One — widely used in single-action automatic pistols — uses an extra power firing pin spring and lightweight firing pin to reduce firing pin inertia. The other type is the firing pin block or drop safety. The firing pin or striker is held in place until the trigger is fully pressed, firing the pistol and moving the firing pin block out of the way. Firing pin blocks are now basically universal.

Introducing Grip Safety

The Colt 1911 handgun had a unique combination of safety features. A grip safety, often found in single-action self-loading pistols, locks the action until the firearm is firmly grasped and the lever is depressed. These prevented a cavalryman from shooting his own horse if the pistol were dropped. And the slide-lock safety allowed carrying the pistol hammer to the rear with safety on, making for a very rapid first shot with increased accuracy.

The slide-lock safety and grip safety were eventually complemented by firing pin blocks or extra power firing pin springs. The original SIG P210 used this type of trigger blocking safety. While effective, they are difficult to use quickly.

One safety feature designed to catch the hammer from falling is the half-cock notch. However, this is not a safe carry position. The half cock notch is not strong enough and would drop the hammer if bumped hard enough. Never carry a single-action pistol on half cock!

Later single-action safety levers sometimes lock the hammer but not the slide and allow the pistol to be loaded while on safe. An uncommon safety feature today is the magazine disconnect. The Browning High Power and Smith & Wesson 39/59/5906 pistols among others use this “magazine safety.” The pistol cannot be fired with the magazine removed.

Safety Features Moving Forward

The iconic handguns of the past have left a lasting legacy on firearm design and safety features. The Walther P38, a trailblazer of the 1930s, introduced the concept of the double-action first-shot design, setting the stage for subsequent handguns like the Beretta 92 combat pistol.

The innovative safety lever of the Walther safely dropped the hammer from full cock. The hammer fell but was blocked from striking the firing pin by the safety itself. Double-action pistols sometimes use two-piece firing pins as well. With the safety applied, the trigger is inoperable, and the hammer cannot rest on the firing pin. This is a very solid system widely adopted.

The SIG decocker is an ergonomic design located in front of the trigger guard. Originally developed in 1938 for the JP Sauer, this lever was necessary as the pistol had a concealed hammer that could not be lowered manually. In the original design, a hard press on the decocker would cock the hammer for single-action fire. This pistol also featured a manual safety on the slide. Slide-mounted safety levers are not as ergonomic as those mounted on the frame but are positive in function. The SIG decocker was adopted for the highly successful SIG P220 and later P series pistols. Though it has safety features, there is no manual safety.

The CZ 75, in its original design, introduces a selective double-action concept, where the safety cannot be applied when the hammer is down. This unique approach ensures the first shot is fired double-action, with subsequent shots allowing for the application of the safety. While not designed explicitly for carrying cocked and safety on, the CZ 75 offers a practical solution for tactical movement without compromising safety.

True Safety

In contemporary times, striker-fired polymer-framed handguns have become immensely popular, with models like the Glock leading the way. These firearms, predominantly double-action-only, prioritize simplicity and reliability. Glock, for instance, incorporates a firing pin block and a trigger lever within the trigger face, preventing lateral discharge if the trigger is snagged. Some models may include a manual safety, offering an additional layer of control for users who prefer it.

However, it’s crucial to understand that while mechanical safeties are valuable, true safety ultimately lies with the shooter. Regardless of the firearm’s design and safety features, responsible gun ownership, proper firearms training and adherence to safety protocols are paramount. 

From the early days of trigger guards and half-cock notches to the sophisticated safety features of modern handguns, each development has contributed to the overarching goal of ensuring firearm safety. The legacy of iconic handguns and the innovations of contemporary designs remind us that safety is not just a feature. It’s a philosophy that embraces a mindset of continuous learning, responsible gun ownership and a commitment to safety.


This article is a compilation of previous blog posts authored by Bob Campbell and Beth Alcazar.