Looking at the best optics on the market, today we review the Primary Arms MD-25 ACSS and the Holosun 503g. Both reticles have more than just a red dot and include amazing ACSS reticles to do multiple functions.

| Get the gear in this review |

Primary Arms MD-25 ACSS

25mm Anti reflection filter

Holosun 503g

Scalarworks 1.93 leap mount

Brownells BRN-180 Upper

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Mantis X10 Elite

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The reason I love these optics so much is that they blend both speed and accuracy. Most optics are a give and take. The red dot dominates the speed spectrum and adding a magnifier helps to give you a bit more accuracy. You then move into the LPVO with a jump in accuracy but you begin some of the speed that you get in the red dot. And finally you have scopes that maximize accuracy at the expense of speed.

The Primary Arms ACSS reticle blends both worlds to land this optic squarely in the center with its CQB style horseshoe to make super-fast shots. And combining the optic with a magnifier, those long-range shots now have all the appropriate holdovers.

So we take a look at which one we like better. We begin by taking a look at the housings. The Holosun 503g uses 6061 aluminum and a 20mm objective window. It uses a t1 optics footprint to connect into the most popular mounts such as the scalarworks 1.93 leap mount. It utilizes the normal adjustment screws to adjust elevation and windage in 0.5 MOA increments. The 503g also uses a standard 2032 battery with a 50k hour life located on the right of the optic.

The Primary Arms MD-25 ACSS also uses 6061 aluminum in his housing construction. The MD-25 ACSS includes a 25mm viewing window for larger peripheral view. The front of the optic also has threads to add the optional Primary Arms GLx anti reflection filter. It also uses a standard 2032 battery but this battery is located within the dial on the left side of the optic. The battery life is listed at 50k hours. The housing uses the same t1 footprint as the holosun 503g for easy swap of different mounts.

Next we looked at the different mounts included with both the MD-25 ACSS and Holosun 503g. The 503g included two mounts, the low mount and the hight mount. The low mount is standard and what you like to see on a PCC and the larger mount is a 1/3 co-witness mount. So if you want a taller mount or absolute co-witness, you need to purchase a different mount.

The MD-25 ACSS also includes two mounts but also has multiple spacers for different heights. The first mount is the low mount for a 0.96 inch rise and then it has the included cantilever mount. The cantilever mount has a rise of 1.41 inches and includes two risers. The thin riser can be used to give you absolute co-witness at 1.53 inches and the thick riser gives you 1/3 co-witness at 1.64 inches.

We then take a look at the function of each of the optics. The holosun 503g is turned on by pressing either the + or – button located on the top of the optic. The 503g can also be turned off by pressing both buttons together for long term storage. As this optic is equipped with shake to wake, this isn’t really needed as I’m going on my same battery for 2 years. You can also hold down the + button to remove the horseshoe if you want a more precision-based reticle that saves some battery. The 503g also has 12 brightness settings that include 2 night vision settings. The 503g is extremely bright even on the brightest day.

The MD-25 ACSS is turned on using the rotary dial for super fast brightness adjustment. The MD-25 does not have shake to wake but with the extreme battery life, it really makes it a moot point. The Primary Arms MD-25 includes two night vision settings and an off setting for a total of 11 brightness settings. The night vision settings were more in tune with NVGs and easier to find thanks to the 25mm aperture.

Hopefully our comparison helps you pick the best red dot for you and with either choice, you’ll end up with an absolutely fantastic option.

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Music by the amazing Barren Gates