Backup Iron Sights (BUIS) allow a shooter to stay in the fight even when their primary optic fails. Outfitting your rifle with an optic like a red dot, reflex sight, or variable power scope offer major benefits, like extended range, easy target acquisition, and better visibility in low light conditions. However, like all mechanical devices, optics can fail. Batteries die, and many optics can be knocked off zero with a hard bump.
With hundreds of options available, from simplistic to ultra-tactical, but our simple guide makes it easy for you so find what you need. Read on to see what our experts recommend and reviews of the top BUIS on the market.
Top BUIS Comparison Table
Buying the Best BUIS for Your Rifle
There are several key factors to consider when shopping for backup iron sights. Understanding some of the basic differences in style, design, and construction will help you narrow down your options and pinpoint the right BUIS for your shooting style.
- Mounting and styles. There are various styles and mountings for BUIS
- Gas block sights mount on a rifle’s gas block, with the front sight resting slightly higher than the rear aperture.
- Rail mount sights mount to the rifle’s railing system with the front and rear sights on a level plane.
- Micro sights are rail mount sights with a lower profile. Often they can be viewed below your primary sight for easy and fast use.
- Offset sights sit at a 45 degree angel from the normal sight line on your gun. This allows them to be used instantly by simply twisting the weapon at an angle if your primary sight fails.
- Folding Sights or Fixed Sights. Iron sights are either fixed or folding. Fixed sights constantly remain in place and ready for use. Folding sights are designed to pop up when deployed. This design doesn’t interfere with the rifle’s primary sighting optic and can protect them from damage when not in use and can be folded up and into place instantaneously when they become necessary. Most shooters prefer a folding design for use as a BUIS.
- Material. Despite a BUIS designation as “iron sights,” they are rarely made of actual iron. The most common BUIS materials are steel, aluminum, or polymer. Steel is durable and rugged but can be heavy and throw off the balance of your weapon. Polymer is lightweight but lacks the toughness of a metal sight. Aluminum provides a nice balance of weight and durability.
Your BUIS aren’t going to serve their purpose if you can’t see them. Most iron sights are black, which makes them difficult to see in low light conditions. Some sights have features that make them more visible.
- High Visibility Sight Posts. One option is a sight with brightly colored posts which create a highly visible contrast when aiming. The contrasting colors make sight alignment easier, but these sights can still be difficult to see in the dark.
- Tritium Night Sights. Tritium is a glow-in-the-dark isotope incorporated into some sights to improve visibility in low light.
Top 3 BUIS Options Reviews
This melonite-finished, all-black backup site provides maximum strength and durability while adding minimal weight and bulk. Both the front and rear sights of the Magpul MBUS PRO BUIS sit at standard AR sight height when deployed, yet sit so low when stored that you’ll forget they are even there. Compatible with all Picatinny rail systems and with most IR aiming laser and light installations, make this BUIS system a smart choice for the serious tactical shooter.
Featuring a dual aperture design, windage adjustable rear, and an elevation adjustable front sight, these may be the most functional and versatile backup sights on the market. If you want durable sights that are invisible when you don’t need them and instantly available when you do, Magpul MBUS PRO is the best BUIS that money can buy.
The easy push-button deployment and spring-loaded design of these BUIS come with a full one-year warranty and dedicated support team. Along with amazing company customer service, these sights come with full windage and elevation adjustability.
With a convenient low profile when folded, these sights do not interfere with maneuverability or your primary optic system. When deployed, these Ozark Armament BUIS are offset by 45 degrees; this allows them to be used in conjunction with other accessories and optics. The offset design enables the shooter to easily switch back and forth from iron sights to optic accessories to fit a variety of shooting scenarios. Truly versatile sights, they allow the shooter to adapt, facilitating rapid transition from close range to long range shooting and back again.
The Dagger Defense tactical backup iron sight fits standard Picatinny rail systems and is easy to mount. Made of aluminum alloy with a black matte finish, these sights can easily be mounted in combination with red dots, holographic sights, and adjustable scopes. The spring-loaded, flip up function allows you instant access to your BUIS with the simple push of a button while keeping them down and out of the way when you don’t need them.
You will be surprised by the quality of these reliable and extremely affordable backup sights. They are as solid, rugged, and reliable as other products with a much heftier price tag. These are top notch sights that will please even the most discerning tactical shooter.