Nightforce ATACR 4-20×50 F1 – C644 Mil-XT



The ATACR™ 4-20×50 first focal plane riflescope fills an important magnification range in the ATACR™ line. It is smaller and lighter than the 5-25×56 F1 while offering a 25% improvement in magnification over the 4-16×42 F1. This 20x max magnification, apex mid-power riflescope can be placed atop a bolt action or a semi-automatic rifle.

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ATACR™ riflescopes are professional tools made to serve tactical professionals, law enforcement, and the military. The ATACR™ family of riflescopes are reliable, repeatable and built from the most rugged materials with mission-critical features. ATACR™ riflescopes are designed to deliver bench rest precision even under the harshest conditions. Available in a wide range of sophisticated first focal plane reticles, in illuminated MOA or MRAD configurations that address virtually any shooting environment, leaving absolutely nothing to chance.

Fully multi-coated ED glass results in superb light transmission, brilliant images, and exceptional color contrast. With the varying magnification ranges, the ATACR™ line of scopes can cover almost any situation a shooter may have. The ATACR™ from Nightforce redefines the “long” in long range, leaving the possibilities endless.

ZeroStop™ technology allows you to create a positive mechanical stopping point at your chosen zero point. Then, no matter how many elevation adjustments you make, turning the elevation knob down to the ZeroStop™ setting returns you to your original zero, completely by feel—even in total darkness or while wearing gloves. No counting clicks, no need for visual reference, and no wasted effort. Just an instant return to zero. Every time.

ATACR™ riflescopes feature digital reticle illumination technology (DigIllum™) designed to increase convenience and functionality in a single-button control. Built into the side focus control, there is no additional width or knobs on the scope. This technology allows you to choose the appropriate illumination setting for your lighting conditions – either red or green, in five intensities from very dim to extremely bright. 

The illumination will turn off automatically after 1 hour or can be manually turned off to extend battery life. When illumination is turned back on, it defaults to your previously chosen setting, ensuring your night vision will not be adversely affected and that you’re instantly ready for a shot.


Body Tube Diameter: 34mm
Overall Length: 13.9 in/353 mm
Mounting Length: 5.9 in/150 mm
Weight: 35.2 oz/998 g


Magnification Range: 4-20x
Focal Plane: First Focal Plane (F1/FFP)
Click Value: .250 MOA or .1 MRAD
Internal Adjustment Range: E: 130 MOA/38 MRAD W: 100 MOA/29 MRAD
Parallax Adjustment: 11 yd–∞
Eye Relief: 3.5 in/90 mm
Field of View @ 100 yd or m: 4x: 23.6 ft/7.9 m 20x: 6.1 ft/2.0 m
Exit Pupil: 4x: 8.3 mm 20x: 2.5 mm
Illumination: Digillum
Elevation Feature: ZeroStop
Power Throw Lever: Standard

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