5 Best Red Dot Sights For FNX 45 Tactical

This guide features 5 best red dot sights for FN 509.  45 ACP shooters trust these products for years, and they're great for both range training and daily concealed carry.

More red dot sights are coming out with new technology. Some cost a lot, while others are priced just right and still offer good quality.

Buying expensive red dot sights for old school FNX 45 Tactical doesn't mean it's one size fits all, so this list include red dot sights at all price points.

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FNX 45 Tactical Red Dot Sights

Holosun 507C - Best Overall

The Holosun 507C fits right into the RMR optic cut on the FNX 45 Tactical, so you don't need any extra pieces. One of the best parts is its big buttons. They're simple to use, even if you have big fingers, and you can see them in the dark.

The battery can work for up to 50,000 hours. And if it stops, there's a solar panel that keeps the sight going.

The user can switch out the battery easily from the side without having to remove the whole sight. Even if the battery stops, the sight won't turn off because of the solar backup. Right now, it's a great deal, making it as good of a choice as the Trijicon RMR.

Trijicon SRO - Largest Sight Window

The Trijicon SRO 5 MOA is perfect for the FNX 45 Tactical and getting on target quickly especially with a longer sight radius. The SRO uses the same RMR base and has an impressive battery life that last more than 4 years, though it's not meant for heavy-duty use in the context of direct impact on the lens repeatedly.

With this sight, you can spot the dot faster and more reliably, even if your pistol draw is a bit off. It also offers automatic brightness settings. You can pick a brightness level and lock it, or let the surrounding light decide for you. A great feature is the top battery compartment.

You can change the battery from the top without removing the sight or resetting it. After each shot, you can spot the dot again quickly, so you don't waste time searching for it. Some people think you need to remove the sight to change the battery, With the SRO, battery changes are hassle-free right from the top without sight removal.

Trijicon RMR Type 2 - Best Durability

The Trijicon RMR Type 2 is the duty grade red dot sight for FNX 45 Tactical for many years. It's designed with a better battery grip, ensuring the dot stays on without any hitches. This red dot sight is made from the super tough 7075 T6 aluminum material, so it can handle drops and other rough handling without breaking.

The Lock Mode on the Trijicon RMR automatically sets the brightness, making it great for concealed carry. It also has two modes that work well with night vision goggles. Its battery can last up to four years, but you should change it yearly. It offers red dot sizes from 1 MOA to 6.5 MOA.

For those with astigmatism, the 6.5 MOA dot is the best pick. Some people might think bigger dots are not precise, but in reality, the 6.5 MOA dot ensures faster target acquisition and a rounder dot.

Trijicon RMR HD - 3rd Gen RMR

The Trijicon RMR HD has a big window, similar to the Trijicon SRO but featuring the original RMR durability that everyone has been begging to design. FNX 45 shooters can finally mount this new RMR and send some mean 45 ACP down range.

The RMR HD also has a special sensor in the front. This sensor changes the brightness of the dot based on the light around your target. So, if you're using a pistol light or if it's really sunny outside, the dot will always have the right brightness for shooting or finding targets in the dark.

Ultimately, the Trijicon RMR HD is bridging the gap between the Trijicon SRO and the RMR type 2.

Swampfox Justice - Best For The Money

Most red dot sights differ from the Swampfox Justice red dot sight. The Swampfox Justice fits perfectly on the FNX 45 Tactical RMR optic plate. Its unique tapered sight design (1 X 27) makes the field of view seem larger, helping users quickly lock onto targets.

The Swampfox Justice red dot sight has a clearer sight picture compared to the Liberty. Like other red dot sights, it gives unlimited eye relief for fast target spotting. Its lightweight, skeletonized body fits most optic-ready holsters, including the ALS series duty holsters. A unique feature of the Justice is its "Shake Awake" technology, which is like the motion sensor in the Holosun 507C.