Primary Arms GLx 2X Prism with ACSS CQB-M5 5.56/.308/5.45 Reticle
- Rifle Scope
- Better rated than 69%
For close to mid-range work with a calibrated cartridge, the always-usable etched reticle and motion-sensing illumination make this a practical prism optic backed by Primary Arms' lifetime warranty.
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How it ranks among the 359 rifle scopes we track
4.7★ across 52 Amazon ratings, Bayesian-smoothed toward the category average.
52 Amazon ratings, weighted on a log scale so huge counts don't drown everything.
Brand identity, imagery, description and spec coverage.
The ProductDome score is separate from the Amazon rating shown above: it combines the Bayesian-smoothed Amazon rating with evidence volume, tracked demand, and data quality across the 359 rifle scopes we track - how the scorecard works · full rifle scopes data report. Confidence: limited - incomplete product information.Last refreshed Jun 22, 2026. Data-computed, not a hands-on test. Compiled by the ProductDome Research Team.
Overview
The Primary Arms GLx 2X Prism is a fixed 2x magnification optic built around the ACSS CQB-M5 reticle, which combines a fast-acquisition horseshoe, center chevron, and bullet drop compensation calibrated for 5.56 NATO, 5.45x39mm, 6.8 SPC, 6.5 Grendel, and select .308 Winchester loads out to 500 yards. It's built for close to mid-range rifle use rather than long-distance precision shooting.
Because the reticle is glass-etched rather than projected, it stays usable even if the illumination fails or the battery dies, which matters for a defensive or duty-oriented optic. The AutoLive system adds motion-sensing power management on top of that, turning illumination on with the slightest movement and powering down when the rifle sits still, aimed at extending battery runtime without the shooter managing it manually.
- Fixed 2x magnification prism
- ACSS CQB-M5 reticle with BDC holdovers
- AutoLive motion-sensing illumination
- Includes mount and 3 risers
Who it's for
Shooters running 5.56, 5.45x39, or similar intermediate cartridges who want a fixed low-power prism with bullet drop compensation built in, rather than a variable-power scope. Not the choice for anyone shooting calibers outside the ACSS CQB-M5's calibration list, since the holdover marks won't line up.
Strengths and trade-offs
Drawn from this product's published specifications.
- Glass-etched reticle works with or without illumination
- AutoLive motion-sensing extends battery runtime
- Holdovers calibrated for multiple intermediate cartridges
- Compatible with standard mini-ACOG style mounts
- Holdover calibration only applies to the cartridges it lists
Performance notes
The reticle combines a horseshoe for fast close-range target acquisition with a center chevron and auto-ranging stadia for holdovers and moving-target leads out to 500 yards. A 42 foot field of view at 100 yards and 3.5 inches of eye relief support both-eyes-open shooting, and the AutoLive illumination cycles through 11 brightness levels while powering down automatically when the rifle is still.
Specifications
| Brand | Primary Arms |
|---|---|
| Model | CQB-M5 |
Other Primary Arms rifle scopes
How it compares
This product against the closest alternatives we track in rifle scopes.
| Product | Amazon rating | Ratings | ProductDome score |
|---|---|---|---|
| Primary Arms GLx 2X Prism with ACSS CQB-M5 5.56/.308/5.45 ReticleThis product | 4.7 / 5 | 52 | 2.7 / 5 |
| UTG 3-12X44 30mm Compact ScopeUTG | 4.5 / 5 | 3,000 | 4.4 / 5 |
| Vortex Optics Diamondback Second Focal PlaneBrand | 4.7 / 5 | 1,500 | 4.3 / 5 |
| PINTY Tactical Rifle Scope Combo: Illuminated OpticsPinty | 4.4 / 5 | 1,100 | 4.3 / 5 |
| Firefield RapidStrike 1-6x24 SFP Riflescope KitFirefield | 4.5 / 5 | 900 | 4.3 / 5 |
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Questions about the Primary Arms CQB-M5
Common buyer questions answered straight from the product spec data - no fluff, no "it depends".
What cartridges is the ACSS CQB-M5 reticle calibrated for?
It's calibrated for 5.56 NATO, 5.45x39mm, 6.8 SPC, 6.5 Grendel, and select .308 Winchester loads out to 500 yards.
Does the Primary Arms GLx 2X Prism work if the illumination battery dies?
Yes, the reticle is glass-etched rather than projected, so it remains visible without illumination.
What mounting hardware comes with the GLx 2X Prism?
It includes 3 risers and a mount compatible with standard mini-ACOG style mounting systems.