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Holosun is a recent comer to the red dot reflex sight arena.  Several well-known and well-respected competitors dominate the red dot reflex sight market. Coming into that competitive arena requires something different.  The Holosun HS501C is accurate, easy to use, has a long battery life, and a very low cost, making the Holosun one of the best values in the category.

Shooters typically consider three factors when choosing a red dot reflex sight for their rifle.

  • Quality and durability
  • Accuracy
  • Battery life

Holosun meets the challenges of quality, durability, and accuracy.  Innovation sets Holosun apart from the rest of the competitors by pairing technology with proven battery design. Using technology as a lever into the market puts Holosun in an incredibly competitive position.

There is little doubt that Holosun has come to the red dot reflex sight market intending to be competitive from the outset.  A look at the features and specifications of the Holosun HS501C red dot reflex sight is proof enough.

Holosun HS501C Sight – Features and Specifications

Shooters who are looking for a red dot holographic sight to mount on a rifle or carbine have features they want in mind. Reviewing the features of the HS501C red dot reflex sight is evidence that Holosun meets the needs of the majority of shooters

Holosun HS501C Features

  • The reticle features a circle and dot configuration.
  • The dot is 2 MOA and is available in either red or green.
  • The 65 MOA Circle makes sight acquisition quick and precise.
  • You can expect up to 50,000 hours of battery life from the Holosun HS501C when setting to the number 6 intensity setting.
  • Twelve intensity settings allow you to operate the Holosun HS501C sight under any light conditions from full bright sun to the using your night vision (NV) equipment.
  • Battery replacement is easy and quick in the tray-style battery compartment.
  • Holosun guarantees shooting comfort and ease with the Holosun’s parallax free optics and unlimited eye relief.
  • The Housing of the HS501C is aluminum with some parts machined from titanium.
  • Each click on the windage and elevation adjustments travels 0.5 MOA.
  • The internal windage and elevation adjustments max out at 50 MOAW

Two features stand out about the Holosun HS501C. Holosun has brought the power of the sun to the red dot sight market.  An integrated solar cell on the top of the sight will keep your red dot working even if the battery fails.

Pair this use of the sun with Holosuns patented Shake Awake technology, and you have the ultimate in battery saving technology.  The sight will sleep the LED during periods of motionless and reactive as soon as any movement is detected.

The Holosun HS501C Specifications and Technical Details

For those of you who are more detailed oriented, spending time in the specifications and technical details of the Holosun HS501C should satisfy you that this is a high-quality sight worthy of being considered among the best on the market.

Reticle2 MOA Dot with 65 MOA Circle
LED Light wavelength650nm
Reticle ColorRed or Green
Parallax errorNone
Eye ReliefUnlimited
Lens CoatingsMulti-coating on all lenses
Battery life50,000 hours
Brightness setting10 DL + NV
Length3.3 inches
Width1.68 inches
Height1.78 inches
Weight4.94 ounces
Water-resistance1m per IP67 specification

Where are holosun optics Built?

Holosun optics are made in China.

How Does the Holosun HS501C Rate Against the Competition?

Making comparisons is sometimes tricky.  Making sure that you are comparing apples to apples is always a challenge.  In this instance, we have tried to choose two of the market leaders that seem to be in the same category of red dot reflex sight as the Holosun HS501C.

Side by Side and Down the Line

 Holosun HS510CCEOTech EXPS2EOTech EXPS2Vortex AMG UH-1
Battery Life50,000 hours600 hours1500 hours
NV CompatibleYesNoYes
Eye ReliefUnlimitedUnlimitedUnlimited
ConstructionAluminum body with Titanium ShroudAluminumAluminum

The Big Three – How Do These Sights Rate?


All three of these sights use high-grade aluminum alloys for the body of their sights.  The Holosun HS501C further enhances the durability and strength of their sight by enclosing it in a titanium hood.

The shroud of any red dot optic is where most of the abuse takes place.  Any additional protection to the shroud of the sight adds to the overall durability and reliability.

Overall, these three sights are nearly equal in their ratings on construction and durability.  Each of these sights is rated for large caliber rifles and will serve well under any circumstances and conditions.

Based on the addition of the titanium shroud, the Holosun HS510C is our pic in this category.


This category is center on the decision on which sight to mount on a rifle.  There are several factors to be considered in this category.

  • Durability
  • Ease of Use
  • Adjustments


Red dot sights are often subject to extremes in climactic and handling.  Patrol rifles spend days traveling in a patrol vehicle ready for use on a moment’s notice.  The ability to hold zero despite these conditions is a significant factor.

Users of each of these red dot sights report how well these sights meet these criteria.  However, The Holosun has a slight disadvantage in this area to the other two sights.  Both the Eotech and the Vortex are closed systems.  The Holosun is an open system that leaves it vulnerable to extreme wet conditions.

Ease of Use

Quick-detach Picatinny rail mounts make swapping out optics quick and easy. Both the EOTech EXPS2 and Vortex UH-1 have quick-detach Picatinny rail mounts. The Holosun doesn’t take the second seat in this category, featuring a non-linear quick-detach Picatinny mount.

Battery changes are also a subject of concern with some shooters. Both the Vortex UH-1 and the EOTech EXPS2 require the removal of a threaded cap to change the battery. The Vortex UH-1 requires the removal of a threaded cap to replace the battery.  The EOTech EXPS2 has a front-mounted battery compartment with a threaded cap.

The Holosun houses the CR2032 battery in a tray that slides in and out of the sight housing.  The tray makes changing the button style battery easier than a battery compartment that requires the sight removal from the gun.

The winner in this category is the Holosun

Controls – Ease of Use

Accessing and using the controls and adjustments on a red dot sight can pose problems for some shooters.  Making sure that you can easily access and manipulate the controls on your sight is an essential factor in your decision.

The EOTech EXPS2 places the controls on three sides of the sight. The NV controls and red dot intensity controls are on the back, facing the shooter.  On the right side are the windage and elevation adjustments.  The intensity and on/off switch located on the left side of the sight.

The Vortex follows a similar pattern placing the on-off buttons on the back facing the shooter.  Windage and elevation adjustments are on the right side of the sight housing. The battery replacement cap is on the left side of the housing.

Holosun opted to keep a cleaner profile for the user.  The intensity, on-off, and reticle selections buttons index on the right side of the housing.  Windage adjustments are on the left side of the housing.  Elevation adjustment controls are on top of the housing in front of the lens.

For ease of use, the Holosun gets the nod in this category.  The primary controls used by the shooter are easily found and manipulated on the right side of the housing.  Since most shooters are right-handed, this puts the controls in a natural position.  The intensity and reticle selection is quick to make without losing a sight picture or dismounting the rifle from a shooting position.

The MOA Factor – Adjustments for Accuracy

Two adjustments in the accuracy of a red dot sight are of interest to shooters.

  • The MOA per click
  • The overall windage and elevation adjustment range

MOA Per Click

The more clicks per MOA of movement in the windage and elevation adjustment translates to a more accurate aim. The standard measure is the MOA per click of the windage and elevation turrets.

Nothing lost or gained in this category.

The amount of travel through the windage and elevation adjustments is vital in some respects.

  • Vortex UH-1 – 100 MOA maximum adjustment for windage and elevation
  • Eotech EXPS2 – 40 MOA total maximum windage and elevation adjustments
  • Holosun HS501C – 50 MOA total maximum windage and elevation adjustments

The Vortex gets the prize in this category.  The Holosun HS501C takes second place with a respectable 50 MOA of travel in both windage and elevation adjustments.

The Big Factor – Price vs. Features

For many shooters, the first test of any purchase is the price to features ratio.  In this case, our choice must be the Holosun HS501C.  The Holosun HS501C is comparable in almost every feature and category with either the Eotech or the Vortex. However, it is half the price.

The addition of the innovative solar technology that enhances battery life is a plus. The Holosun Shake Awake technology puts the Holosun one step ahead for most shooters.  The clincher on this decision is the price point.

The Holosun price is little more than half the price of the other two comparable sights.  Under regular use, the Holosun HS501C performs as well or better than the EOTech or the Vortex.  Our choice is the Holosun HS501C red dot sight.

The Decision is Still Yours

In the end, you must make your own decision.  We hope that this article helps you make a more informed decision.  Finding the red dot sight that best fits your needs and applications is an important thing.  Good Shooting!