There’s a lot more to handgun sights than meets the eye. OK, so that little play on words was entirely on purpose, but it’s true. While sights seem simple and even mundane, there’s quite a bit of thought and sophisticated science put into the design of effective handgun sights.
As an example case, we’ll use the Beretta PX4 Compact Carry Model. This pistol has been optimized for concealed carry, so there are some plenty of “sight features” designed to make it perform in all sorts of conditions. Can we skip the absolute basic role of handgun sights which is to line up the barrel with the target? If so, let’s dive into some of the more advanced factors.
Visibility in Daytime
Being able to see sights clearly in the daytime sounds deceptively simple, doesn’t it? It might be, or it might not. Consider the case of old-school iron sights - a simple black front post with a black rear notch. The works great in daylight conditions provided that your target is not also dark. If it is, you might not be able to see your sights at all, or at a minimum, not very well. This is one of the reasons that many standard “iron sight” configurations have white dot inserts or paint on the front post and to the sides of the rear notch. For precision against a lighter-colored target, you can use the sharply defined iron sights. Against a darker background, those white dots will show up pretty well.
On our example pistol, the PX4 Compact Carry, Beretta took a different approach that provides even better daytime visibility again a wide variety of target background colors. The oversized front dot on this pistol is a "hazard" or "construction zone" orange. Actually, it’s not even a dot. The shape is square, which allows the orange area to be even larger, extending almost all the way to the sides of the wide front sight post. I find that the use of this dramatic orange color provides better visibility than even traditional bright white dots.
Visibility in the Dark
Sights on pistols designed for concealed carry need to work in dark conditions since that’s when many self-defense encounters occur, either on the streets or in the home. The traditional solution to “night sight” capability is to use Tritium inserts in the front (and sometimes rear) sights. In very dark conditions, the slight radioactive energy glows in a green or sometimes amber color, allowing you to see the sight alignment. The big benefit to using Tritium is that it requires no power source and runs continuously for seven years or so. Keep in mind that Tritium works well in very dark conditions but is not so visible in transitional light conditions. That’s why the combination of the large orange “dot” with a center Tritium insert works so well.
There’s an alternate and less expensive approach that you’ll see on many pistols. Rather than using Tritium inserts, which can add a hundred dollars give or take to the total cost of a handgun, some guns use photo-luminescent paint or inserts. This material collects light and glows in the dark for a period of time, usually 15 to 30 minutes give or take. If you’re transitioning from a light to a dark environment, that may be enough to cover you. If you’re a military or law enforcement user and know when you're headed into potential trouble, you can “charge” your sights with a flashlight before entering a dark area. The drawback to this approach is when you might find yourself in dark conditions for extended periods of time. That’s when Tritium might be a better solution.
Speed of Acquisition
In defensive situations, being able to acquire and line up your sights quickly might mean the difference between life and death. Sight manufacturers use many techniques to support the human eye’s natural features and tendencies.
We already talked about color for daylight visibility. The precise and deliberate use of specific color shades, like the “construction” orange shade on this PX4, can improve speed too. By giving your eye something unique on which to focus against a cluttered background, you can find the sight more quickly. It’s all about providing contrast by using a color that the eye sees easily, and that is different from other shades in the surrounding environment.
The rear sight design has a lot to do with speed too. In the relatively recent past, the trend was to flank the rear notch with colored or Tritium dots. The idea was to provide a three-dot approach that would allow the user to quickly line up front and rear sights in daylight or dark conditions. However, given the disproportional importance of front sight focus, many sight makers are now “blacking out” the rear sight assembly. The notch is still there but gone are the dots or Tritium lamps on the rear sight. The idea is that what you quickly raise the handgun into view, your eye can easily pick up the front sight without the visual clutter of multiple dots on the front and back. That’s why the PX4 Compact Carry shown here uses a simple, all black, rear notch sight. When you raise it into view, that large orange front sight will leap into view, allowing a faster first shot.
On some rear notch-type sights, you’ll see that the corners in the bottom of the notch are rounded or, in some cases, the entire rear notch is U-shaped. That’s because what the eye really needs to see is the top edge. That’s the part that lines up with the top edge of the front sight. With no sharp corners at the bottom of the rear sight, your eye tends to find and focus immediately on the top corners. It’s just a small detail that improves the speed at which you can line up your sights properly.
Another fairly recent trend involves the shape of the rear sight housing. For a long time, combat rear sights were ramped with the sight body melting into the slide at the leading edge of the rear sight housing. The idea was to reduce snag potential. However, when you think about it, the primary detriment to snagging is during the draw, when the handgun is moving in the opposite direction of that ramped sight. The ramp doesn’t help in that case.
Concealed carry pistols like the PX4 Compact Carry will often feature a hard leading edge of the rear sight. This feature facilitates one-handed operation of the pistol if necessary. If you need to rack the slide or clear a malfunction but only have use of your firing hand, you can use that edge of the rear sight as a leverage point.
The next time you’re shopping for pistols, spend some time carefully looking at the different sight designs. Raise the handgun into view multiple times from a low-ready position to see how quickly your eyes pick up the sights. Try aiming the pistol at different types of safe backgrounds to see how well the sights contrast. You might be amazed how little details can make a big difference in how effectively your eye can use different types of sights.