Holosun 512C: 5,000 Rounds Later

Holosun makes great-quality optics for both rifles, shotguns, and handguns. This is not news to anyone, and they don’t really need any introduction, do they? But are you familiar with the 512C enclosed reflex sight? I’ve had one for some time now, and it’s held up surprisingly well. I recently moved it from one of my ARs to the PSA JAKL for a training event and found a cool fact.

I try to keep track of how many rounds I put through each gun and optic for review purposes. When I pulled up the 512C, I realized it was only 400 rounds away from reaching the 5,000-round mark. I decided to give it one more spin on the AR to see if it was still holding its zero. I zeroed it the day I placed it on my rifle and used it regularly. 5,000 rounds in, and it’s still using the same battery, and it’s been in a variety of temperatures during training events.

Holosun HS 512C Red Dot.
After 5,000 rounds, the Holosun 512 has been a great quality optic that continues to run strong. [Photo: Jason Mosher]
I can’t recall specifically hitting the optic on anything, but it’s been thrown in rifle cases with other rifles or just tossed in the back seat with other gear. I hadn’t paid attention to the ammo count and was surprised to see it was climbing that high. So, I headed to the range with my trusty 512C for a 400-round fun day.

I did some plinking and a few drills, but like always, the ammo disappeared way too fast. The good news, however, was that the optic was still fine-tuned and running flawlessly. Now, it begins its journey with the PSA 5.56 JAKL. I thought this would be a good time to take another look at the Holosun 512C reflex sight.

Holosun 512C Enclosed Reflex Optic

The Holosun 512C is a somewhat boxy-looking optic, which I like. It measures 3.35 inches in length by 1.66 inches wide and 2.27 inches high. I also like its window size, which is 0.91 x 1.26 inches. That’s a lot of glass for a nice sight picture. Along with that large window is a great reticle, which consists of a large circle around a center dot. It’s multilayer reflective coated as well.

Holosun HS 512C Red Dot.
Changing the battery on the 512 is easy via a side-loading compartment. [Photo: Jason Mosher]
You can change the reticle setting from a dot-only to a circle-only reticle or a circle-and-dot reticle, depending on your needs and preferences. The dot is 2 MOA, and the circle is a whopping 65 MOA. Looking through it is a little like looking through an EOTech; it’s parallax-free with unlimited eye relief.

Another thing I like about Holosun optics is that most of them have “Shake Awake” technology, which automatically activates the optic when it senses motion and shuts it down after 10 minutes if the weapon is idle. When you pick the gun up, the optic turns back on and is ready to go. This really helps with battery life because I always forget to turn off my optics.

Battery life and Solar Failsafe features

The 512C runs on a CR2032 battery and has a battery life of 50,000 hours. Even if the optic did not turn off, this is a great run time. However, with the Shake Awake mode, it makes sure those 50,000 hours are not being used sitting in the safe. To change the battery, Holosun used a side-loading tray that slides out from the right side of the optic. No tools are needed; just undo the latch and pull it out.

Holosun HS 512C Red Dot.
The Solar Failsafe feature keeps the 512 running much longer than the already impressive 50,000-hour battery life. [Photo: Jason Mosher]
Along with an impressive 50,000-hour battery life, the 512C features Holosun’s Solar Failsafe technology. This feature provides power to the optic when it’s in auto mode and drastically extends the battery’s service life. This is probably why I have never had to change the battery in mine yet.

Operating the 512C Reflex Sight

Using the controls on the Holosun 512 again reminds me of the Eotech HWS 512. The buttons are on the side compared to the back, like those on an EOTech, but they are larger round buttons that are easy to use—even with gloves on. If the optic is turned off, just push either button to turn it on and press both quickly to turn it back off.

Holosun HS 512C Red Dot.
Two large round buttons make operating the Holosun 512C easy, even with gloves on. [Photo: Jason Mosher]
To change the settings on the 512C, press the plus or minus button quickly to adjust the brightness or the reticle. Press and hold the minus button to choose from the three reticle settings that I mentioned in the beginning. Pressing and holding the “plus” button for a few seconds activates an auto mode. When this is activated, the reticle will adjust to the light around it automatically. I prefer to adjust mine manually, but it’s a nice feature to have.

Holsoun 512C Range Performance

As I mentioned above, I’ve had this optic on one of my ARs for a while now. I took it to the range to cross over that 5,000-round mark and then moved it to the JAKL. I had to make a few adjustments to zero it on the JAKL, but that didn’t take long. The elevation screw is on the back of the optic, and the windage is on the right. Holosun provides a small sight key with a small flathead screwdriver on it for this purpose.

I wasn’t surprised the 512 was still zeroed in and running after 5,000 rounds, but it’s still an impressive feat. It has a few scratches on it from being used at training events, but it has held up very well. Even though an AR-15 doesn’t have much recoil, it’s still a lot of movement and vibration for an optic to go through.

Holosun HS 512C Red Dot.
The reticle on the Holosun 512 reminds me of the EOTech HWS 512. [Photo: Jason Mosher]
It’s rated for 1000G vibration and is IP67 submersion rated as well. It’s just a tough optic all around. The circle and dot reticle are probably one of my favorite features of the optic. I use an Eotech on my Daniel Defense, so it keeps both optics familiar to me. Once I sighted in the JAKL, I did some plinked with that as well, and it’s off to a good start. I plan to keep it on the JAKL for a while so I can rack up some more rounds with the 512.

Worth Every Penny

I compare this optic a lot to the EOTech 512 because they have a few things in common. The function buttons, window size, and reticle are all similar. It retails for about $300, making it a great alternative to the EOTech if you don’t want to spend several hundred more. It appears to be built well, and it’s held up great for me. For the price, I don’t think you can find a better deal. This would make a great optic for any AR-style rifle or even a shotgun. It’s worth checking out the next time you’re shopping for a red dot optic.

Jason Mosher is a former three-term Sheriff, law enforcement generalist instructor, and firearms & tactical weapons trainer. Jason graduated from FBI-LEEDA, and holds multiple degrees in subjects ranging from law enforcement administration, business management, to marketing and agriculture. As a writer and law enforcement trainer, he enjoys time on the range, a good WWII book (or movie) and cooking steak on the grill with some friends. As an avid supporter of the constitution and the right to bear arms, his passion is to help educate others while continuing to learn and improve his own skills.
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