Details
NcSTAR AR15 Detachable Rear Sight
The NcSTAR AR15 Detachable Rear Sight mounts to Picatinny rail equipped upper receivers and provides elevation and windage adjustments for zeroing iron sights. The dual aperture design gives you two sight picture options, a larger aperture for fast target acquisition at close range and a smaller aperture for precise aiming at distance. The steel rail clamp and large thumb nut lock the sight securely to the rail without requiring tools for installation or removal. The aluminum and steel construction provides durability while keeping weight reasonable, and the black finish resists wear from handling and environmental exposure.
Key Features
- Dual aperture design for close and distance shooting
- Elevation and windage adjustments for zeroing
- Steel rail clamp with large thumb nut for secure attachment
- Tool free installation and removal
- Aluminum and steel construction for durability
- Black finish resists wear and corrosion
- Compatible with Picatinny rail equipped AR15 upper receivers
- Low profile design allows optic co witnessing
- Manufactured by NcSTAR
Perfect For
- AR15 builds needing backup iron sights
- A1 and A2 replica builds
- Shooters preferring adjustable iron sights over fixed carry handle sights
- Backup sighting when primary optics fail or lose power
Dual Aperture System
The dual aperture gives you two sight picture options without changing components. The larger aperture allows more light through and creates a wider field of view, which speeds up target acquisition when shooting at close range or moving targets. The smaller aperture reduces the sight picture and forces more precise alignment, which improves accuracy at distance where small aiming errors are magnified. You flip between apertures based on the shooting situation without tools or adjustment.
Elevation and Windage Adjustments
The elevation adjustment raises or lowers the point of impact vertically, while the windage adjustment moves it left or right. These adjustments let you zero the sights to match your ammunition and shooting distance, compensating for barrel harmonics, bullet drop, and wind drift. The adjustments click in defined increments so you can track changes and return to a known zero. Once zeroed, the settings hold their position during firing and handling.
Steel Rail Clamp and Thumb Nut
The steel rail clamp locks into the Picatinny rail slots and applies clamping force across the width of the rail, which prevents the sight from shifting under recoil. The large thumb nut provides leverage for hand tightening without requiring a wrench or screwdriver, which means you can install or remove the sight in the field without tools. The steel construction resists wear from repeated installation and handles the impact forces generated during firing.
Low Profile for Optic Compatibility
The sight sits low enough on the rail that you can mount red dot, holographic, or magnified optics in front of or behind it without obstruction. This allows for co witnessing, where the iron sights are visible through the optic at the lower third or absolute co witness height. If the optic fails or runs out of battery, you can use the iron sights without removing the optic. The compact design also reduces snag points when moving through tight spaces or storing the rifle.
Aluminum and Steel Construction
The body uses aluminum to keep weight down while the critical stress points like the rail clamp and aperture assembly use steel for added strength. This combination balances durability with weight savings, keeping the rear sight light enough that it does not shift the rifle's balance point rearward. The black finish is applied to both materials and provides a uniform appearance while protecting against corrosion and scratches.
Picatinny Rail Compatibility
This sight fits any Picatinny rail that meets MIL STD 1913 specifications, which includes the majority of AR15 flat top upper receivers. The rail clamp is sized to fit the standard slot spacing and recoil lug dimensions, so the sight locks securely without excessive force or modification. Verify your upper receiver has a Picatinny rail rather than a proprietary rail system before purchasing.
Follow safe handling and manufacturer instructions. Ensure compliance with all applicable laws. Verify rail compatibility before installation. Torque thumb nut securely to prevent sight movement during firing. Confirm zero after installation or removal.
