Why only 3 dot sights

[emonsteadman]

I was wondering if anyone knows why there are predominantly only 3 dot sights for pistols.
I was trying some pistols out at the range and was typically shooting low. This was because I was trying to alight the 3 dots in line, rather than aligning the top of the front sight with the top of the back sight.

Are there any sights with horizontal lines on the sides instead of dots? It would make the sight picture look like this:
-- o --
Why are there only 3 dot sights?!

[BehindBlueI's]

There are multiple alternatives, some more widely available than others.

Two dot set which makes a sorta-kinda-8 shape (such as Heinie's "straight 8" sights)
A lined square cut rear sight with a dot front sight, black front sight, or color insert front sight (such as Glock OEM or S&W revolver OEM)
Plain rear with high visiblity front (such as Dawson Precision fiber optics)
Bar and dot, similar to the 8-shape but the bottom is replaced with a line (Novak bar/dot set)
Von Stavenhagen sights, which have a vertical line in the rear and a dot in the front (old school Sig or Walther OEM sights)

Etc. etc.

[RevolverRob]

The best sights for target work are plain black post and notch sights with serrations on them, where the rear notch and front post are fairly narrow. Unfortunately, those sights work best in good light and medium to not at all in compromised light.

But bear in mind, that even 3-dot sights can be sighted differently. Some folks, like me, just use the dots as a reference to confirm vertical and horizontal alignment, while using the top of the sight to aim (#2). Others "drive-the-dot", where the point of impact is behind the dot (#3 in the image below).

I'm a big believer in using the sights and sighting metric that is most intuitive to you. For me "drive-the-dot" has never worked. That's basically because I grew up using ramped or partridge front sights with a notch rear and not a dot that covered my target (e.g. sight picture #2). For me the top of an arrow, triangle, line, or ramp makes the most sense for precision work. For fast work, a front dot with plain black or vertical bar rear works very well.

Anyways, if your brain thinks o-o-o where the center o should cover the target makes sense, you can get 3-dots setup precisely like that.

[Erick Gelhaus]

Why are there only 3 dot sights?!

One on each portion of the sights - left, front, right.

For many years, Innovative Weaponry Inc (the original IWI) did a tririum front over a horizontal line at the bottom of the rwar notch, very much like the Spaulding CAP-LE sights today.

[Rex G]

Don’t forget the revolver sights with several elevation marks on the front sight, best done as gold insets.

[HopetonBrown]

The best sights for target work are plain black post and notch sights with serrations on them, where the rear notch and front post are fairly narrow. Unfortunately, those sights work best in good light and medium to not at all in compromised light.

The Travis Haley sights are 125 front/125 rear like traditional target sights, and have tritium if people are looking for that set up.