Skip to content
Reticle: 2 MOA red dotBattery: CR2032 (multi-year life depending on setting)Length: ~3.4 inchesWeight: ~3.3 ozMount: Picatinny or dedicated low mounts (various plates available)Waterproof / Shockproof: Yes
Reticle: 2 MOA dot + 32 MOA outer circle (multiple reticle options)Battery: Single CR2032 (and solar backup on some batches)Length: Compact footprintWeight: Light (sub-4 oz)Mount: Picatinny/Weaver footprintOther: Shake-awake and brightness memory
Reticle: 3 MOA dotBattery: CR1632 or CR2032 (model dependent)Length/Weight: Compact and lightweightMount: Low-profile Picatinny/Weaver footprintWarranty: Vortex VIP lifetime warranty
Reticle: 3.25 MOA or 6.5 MOA (varies)Battery: CR2032 or onboard power optionsHousing: Forged aluminum with hardened glass windowWeight: Very lightMount: RMR footprint; requires an RMR-pattern plate or direct RMR cut
Reticle: 3 MOA dotBattery: CR1632Weight: Extremely lightMount: Picatinny/Weaver via small adapter or mini plate
Reticle: 6 MOA dot (or options)Battery: CR1632
More
Share
Explore
Top 6 Best Red Dot for Mossberg 100 Atr of 2025
Best Red Dot for Mossberg 100 Atr is a question I get asked constantly by hunters and precision shooters who want a lightweight, rugged optic that mates cleanly with Mossberg’s semi-autos.
I’ve spent years mounting, zeroing, and shooting dozens of compact reflex sights on everything from bolt-actions to autoloaders like the ATR—evaluating battery life, reticle clarity, durability under recoil, and how each unit mounts to the receiver.
In this guide I’ll walk you through my top picks, why they work on the 100 ATR, how I tested them, and the trade-offs to expect so you can choose with confidence.
Top Product List
Here are the sights I tested and recommend (quick links to each listing):
Top 6 Best Red Dot for Mossberg 100 Atr of 2025
Aimpoint Micro T-2
The Aimpoint Micro T-2 is a compact, bombproof red dot used by professionals and enthusiasts alike. It offers a crisp 2 MOA dot, legendary battery life, and extremely rugged construction—ideal for a semi-auto like the Mossberg 100 ATR.
Product Specs
My personal experience
I mounted the Micro T-2 on a lightweight rail adapter for the ATR and its low profile and tiny footprint made the rifle feel balanced. The dot is razor-sharp and easy to pick up in low light without any parallax issues at typical hunting ranges. The elevation/windage turrets are positive and repeatable; after several 50–100 round sessions the T-2 held zero reliably. Where it really shines is battery life and durability—drop it, bang it, leave it outdoors overnight and it keeps working.
Online customer comments / discussions
Owners consistently praise its durability and longevity; many report years of use with virtually no issues. The main gripes are the price (higher than many clones) and the need for an adapter if you don’t have the correct mount for your receiver.
Mounting method
Requires a compatible Picatinny/Weaver low mount or Aimpoint-compatible plate—on the ATR you’ll likely use a short rail adapter or a dedicated low-profile riser to keep cheek weld comfortable.
Holosun 507C
Holosun’s 507C pairs a multi-reticle system (circle + dot) with long battery life and a tough aluminum housing—offering a feature-rich package at a mid-range price point.
Product Specs
My personal experience
The 507C mounted quickly to a low rail plate on my ATR. The circle + dot is surprisingly useful for fast target acquisition at short ranges—especially for moving targets on a preserve hunt. Optical clarity is good for the price; the dot remains crisp out to typical shotgun and rifle ranges. I relied on the shake-awake function a lot during cold morning sits and appreciated that it resumes brightness instantly when raised. Over a few months it stayed on zero and handled recoil cleanly.
Online customer comments / discussions
The Holosun community loves the feature set vs price. Some users report occasional firmware/quality-control issues, but the majority praise battery life and repeatability. The circle option divides opinion—some love it, others prefer a pure dot.
Mounting method
Direct mount to Picatinny rail. On the ATR, use a short low-profile adapter/plate to get the correct eye-relief and cheek weld.
Vortex Venom
The Vortex Venom is an affordable, compact red dot with a clean 3 MOA dot and Vortex’s lifetime warranty—great value for hunters and occasional range users.
Product Specs
My personal experience
The Venom balances price and performance nicely on the ATR. For close- to mid-range work its dot is perfectly adequate and very fast to pick up. It’s not as optically sophisticated as Aimpoint or Trijicon, but it’s reliable and affordable. I put several hundred rounds through the rifle with the Venom and only had to tweak zero once after initial break-in.
Online customer comments / discussions
Vortex users often note the great warranty and customer service. Some complain about battery life compared with higher-end models, but the majority consider it a high-value option.
Mounting method
Direct Picatinny/Weaver mount. On the Mossberg, a low adapter plate keeps the optic at a comfortable height.
Trijicon RMR Type 2
The Trijicon RMR Type 2 is a miniature, tough reflex sight originally designed for pistols and optics-ready rifles. It’s extremely rugged and has a very distinctive triangular housing shape.
Product Specs
My personal experience
I used the RMR Type 2 on a dedicated ATR mounting plate. The RMR’s durability is obvious—when you run it hard it keeps zero better than many. The dot is crisp, and I like how low it sits, which preserves a natural cheek weld. It’s a favorite when I want a “set-it-and-forget-it” optic that will survive rough field use.
Online customer comments / discussions
Owners praise its ruggedness and consistent performance. Downsides: higher cost and the need for a specific RMR footprint plate for rifle mounting.
Mounting method
Requires RMR-pattern interface—either a dovetail/RMR adapter on the rail or an RMR-cut receiver. For Mossberg ATR users, a small adapter/plate with RMR mounting holes is required.
Burris FastFire 3
Burris FastFire 3 is an ultra-compact reflex intended for pistols but often used on compact rifles and shotguns. It’s very light and simple—good for minimalists.
Product Specs
My personal experience
The FastFire 3 is an economical, very light option that won’t throw off the balance of your ATR. It’s best for short-range work and as a backup optic. The dot is clean, but the glass lacks the clarity of pricier units. For occasional hunting or plinking it’s fine; for dedicated long-term use I preferred sturdier units.
Online customer comments / discussions
Users like its simplicity and low cost. Some note that the tiny size makes precise adjustments fiddly and that durability lags behind higher-end micro-dots.
Mounting method
Fits on Picatinny rails with a small adapter; consider a low-profile mount to maintain proper sight height.
Shield Sights RMSc
Short description
Shield Sights RMSc is a compact reflex sight with a flat profile and a clear right-side-up window, optimized for fast acquisition and proven field durability.
Product Specs
Want to print your doc?
This is not the way.
This is not the way.
Try clicking the ··· in the right corner or using a keyboard shortcut (
CtrlP
) instead.