– a small projecting tongue in a firearm that, when pressed by the finger, actuates the mechanism that discharges the weapon.
Pulling, or more accurately, pressing, a trigger sounds like such a simple thing, doesn’t it? Yank that thing backward and you can’t help but hit whatever you were aiming at, right?
If that were true, then shooting accurately would be really, really easy, because, let’s face it, aiming is not all that hard. The hard part is keeping the gun aligned properly until the bullet is on its way down range.
Like most things in life, it’s not nearly so simple. A good trigger can make all the difference in a gun’s accuracy. It does nothing to alter the launch and subsequent flight of a bullet, but it has everything to do with helping the shooter to fire the gun with repeatable precision. That’s because guns are rarely bolted to the bench. Since they’re handheld tools, any movement of any part of the gun during the firing process can impact the alignment of the bore with the target up until the point where the bullet leaves the barrel. A trigger that requires many pounds of force to release, or one that is rough and jerky, can impart just enough movement to the firing platform to cause a miss.
As a result, a high-quality trigger is a big deal. Precise design, engineering, and construction are worth their weight in gold. But there’s a lot more to a quality trigger design than just smoothness of operation. Yes, a trigger causes the release of either a hammer or striker, enabling it to hit a firing pin, causing detonation of the primer in a cartridge, which then ignites the powder. The (relatively) small amount of energy of a trigger press enables the release of a much larger amount of energy. A good trigger often has additional functions.
A good trigger must…
In many gun designs, a trigger also provides the cocking function. We tend to make that whole single-action vs. double-action discussion far too confusing. Think of the difference this way. With a single-action gun, like a Ruger Super Blackhawk or 1911, the trigger does just one, or a “single” thing. It releases the already cocked hammer. In a double-action design like a Smith & Wesson Model 66 Combat Magnum, the trigger can also release a pre-cocked hammer, but it can also be used to cock AND release the hammer. That’s two actions, hence the term double-action. Within double-action designs, there are handguns that can only fire in double-action mode (Double Action Only or DAO) and double-action / single-action mode (DA/SA).
It must be designed to be accident proof. A drop, bump, or other type of impact should not cause a trigger to release prematurely.