TFB Review: Primary Arms Classic RD-25 Red Dot Sight – Push Button Operation

Doug E
by Doug E
Primary Arms CLx RD-25 Review

Primary Arms recently added the Classic RD-25 Red Dot Sight that features push button operation to their lineup, which contrasts the knob-operated PA MD-25 in the SLx series. The new 25mm push button red dot sight harkens back to the style of early reflex sights like the Bushnell TRS-25, Aimpoints, hence its position in Primary Arms’ Classic Series of optics. This affordable 1x optic packs some surprising features for $129.99, so let’s dive in.

Primary Arms @ TFB


As alluded to in the name, the RD-25 red dot features a 25mm window, housed in an aluminum body, which is affixed to a quick detach (QD) Picatinny rail mount. The ON, OFF, and brightness settings round out the “Push Button” aspect of the naming scheme, while the windage and elevation adjustments protrude in their own turrets for easy access. The adjustment knobs are flush with the turrets so they don’t get bumped. Each click adjusts the point of aim by 0.5 MOA. The battery compartment extends from the right side of the housing and adds to the classic styling of the older red dot sights.

Primary Arms Reflex Sights
Primary Arms Classic RD-25 Red Dot Sight Review

Although there’s no official confirmation in Primary Arms’ literature, the Classic RD-25 Red Dot Sight shares the Aimpoint T2 footprint for mounting options. The mounting screws should be tightened to 15 inch pounds when swapping mounts.

Primary Arms Classic RD-25 red dot uses same footprint as the Aimpoint T2.

I am thoroughly impressed by the quick detach Picatinny mount. I’m either behind the times and Primary Arms is only following trends, or they knocked the quick detach aspect on the RD-25 out of the park. The adjustability takes some intentional maneuvering, but it’s easy to properly size it to fit snugly on a rail. When throwing the clamp lever into the locking position, a protruding locking tab fits through the hole on the clamp lever and locks it in place. The locking tab is spring-loaded and can be unlocked by pushing it rearward to release the clamp lever. Apparently I am behind the times as there are several different clamp locking designs, but Primary Arms’ approach works well and I’m glad they added this feature over a friction-only lock that could come undone by snagging on gear.

To adjust the RD-25 QD Mount's Picatinny clamp, push inward on the spring-loaded bar that locks the screw. Once it's out of the way, you can adjust the nut to tighten or loosen it.

The supplied QD mount from Primary Arms was built for an absolute co-witness with iron sights. The photo below shows the RD-25’s 3-MOA dot co-witnessing my Magpul MBUS sights.

Primary Arms Classic RD-25 QD Mount with Absolute Co-witness.
Base QD Mount
Battery Type CR2032 3V Lithium Coin
Brand Primary Arms
Brightness 10 Settings
Click Value 1/2 MOA
Color Black
Finish Hardcoat Anodized
Manufacturer Primary Arms
Material Aluminum
Night Vision Compatible Night Vision Compatible
Optic Series Classic
Reticle 3 MOA Dot
Reticle Color Red
Warranty Lifetime
Weight 7 Oz.
  • 3 MOA red dot reticle
  • Large 25mm aperture for wide field of view
  • Top mounted buttons for brightness adjustment with 10 levels
  • Durable aluminum housing with black anodized finish
  • Fully multi-coated anti-reflective lens
  • Fog resistant and IP67 rated
  • Uses a single CR2032 battery
  • 25,000 Hour battery life on medium setting
  • Includes a ruggedized QD mount
  • Weighs 7 ounces with mount
  • Lifetime warranty


The RD-25’s push button feature works great and is just as intuitive as adjustments on pistol red dot sights. The placement of the brightness adjustments on top was a great idea since you can reach it easily with either hand, compared to some earlier models that made for awkward adjustments on one side. The Primary Arms RD-25 remembers which brightness setting you left it at when you last shut it off, which makes it much quicker than older red dot sights that had 0-11 rheostat brightness settings without any off settings in between. If the RD-25 is switched off, pressing either the plus or minus button turns it on.

I later moved the Inforce WML since it partially obscured the view.

Aside from the push button operation, the Classic RD-25 Red Dot functions just like the one-power red dots of old. I had mounted the RD-25 on the Bear Creek BC15 upper with a 16-inch cold hammer forged barrel (review on that coming soon). I did some up-close drills from 10 to 50 yards and the RD-25’s dot was quick to pick up from low-ready and retention positions that led to first round hits on steel. I then reached out to the 200-yard range from standing and was making consistent hits on my MK Machining Covid Steel Target.

The PA RD-25 RDS atop the Bear Creek Arsenal BC15 upper receiver with a 16-inch cold hammer forged barrel.
Primary Arms Classic RD-25 Review
Ringing steel at 200 yards offhand was a breeze with the PA CLx RD-25.


I was completely satisfied with the RD-25’s performance, and I was pleased by the affordable price tag of $129.99 listed on While the Aimpoint footprint makes sense for having a wide array of aftermarket options, some of those options can get kind of pricey compared to the cost of the optic. However, Primary Arms offers five different discounted mounting options available when purchasing this red dot directly from PA’s website.

The PA Classic RD-25 is a great option with its robust construction, rock-solid mount and quick dot acquisition. If you’re in the market for a red dot sight for home defense, plinking, hunting or pest control, I recommend the RD-25! You can find the product page HERE, or view their whole lineup of optics and accessories at

What do you think about the Primary Arms CLx RD-25 Red Dot Sight? If you’ve already grabbed one for yourself, how has your experience been?

Doug E
Doug E

Doug has been a firearms enthusiast since age 16 after getting to shoot with a friend. Since then he's taken many others out to the range for their first time. He is a husband, father, grandfather, police officer, outdoorsman, artist and a student of history. Doug has been a TFB reader from the start and is happy to be a contributor of content. Doug can be reached at battleshipgrey61 AT, or battleshipgrey61 on Instagram.

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3 of 11 comments
  • Major Tom Major Tom on Nov 02, 2023

    Your red dot and iron sights are misaligned in the cowitness pic. Shall I just chalk it down to camera n00bery?

    • BattleshipGrey BattleshipGrey on Nov 02, 2023

      @Major Tom It's just the camera angle. I was free handing the camera and the upper.

  • Dave Dave on Nov 02, 2023

    I was actually just looking at one of these for an ar9 upper I'm planning. That's fate, that means I have to buy it.