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Start with a product family, then choose two records. Differences, sources, and documentation gaps stay visible.
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Compare factory optic-ready pistol configurations.
Step 2
Select two duty pistols
Step 3
Review the differences
“Not documented” means Known Ground has not verified that field. It is not a zero, “none,” or compatibility claim.
| Attribute | FNFN 509 TacticalSpecs checked Jul 23, 2026 | Beretta92X RDOSpecs checked Jul 23, 2026 |
|---|---|---|
| Typical price | Not documented | Not documented |
| Weight | 27.9 oz | 33.3 oz unloaded |
| Overall dimensions | 7.9 × 1.35 × 5.75 in | 8.5 × 1.5 × 5.4 in |
| Product format | pistol | pistol |
| Mount / compatibility | FN Low-Profile Optics-Mounting System | Beretta 90 Series RDO plate system |
| Catalog status | current | current |
| Accessory rail | MIL-STD-1913 | MIL-STD-1913 |
| Action | Striker-fired DAO | Double-action/single-action |
| Barrel length | 4.5 in threaded | 4.7 in |
| Caliber | 9 mm | 9×19 mm |
| Capacity | 17 or 24 rounds; 10-round configurations available | 18 rounds; 10, 15, or 17-round configurations |
| Controls | Ambidextrous slide stop and magazine release | Ambidextrous slide-mounted decocker/safety or decocker-only, by model |
| Frame | Polymer | Aluminum Vertec frame |
| Grip | Not documented | Vertec panels with wraparound grip included |
| Operating system | Not documented | Short recoil with falling locking block |
| Optics interface | FN Low-Profile Optics-Mounting System | Beretta 90 Series RDO plate system |
| Safety | Internal passive safeties; no manual safety | Automatic firing-pin block |
| Sights | Suppressor-height night sights | Removable front and rear sights |
| Slide | Not documented | Steel RDO slide |
| Thread pitch | 1/2 × 28 | Not documented |
| Trigger pull | 5.5–7.5 lb | Not documented |
Editorial context
Choose by use case, not scoreboard.
FN 509 Tactical: Factory optic-ready tactical configuration.
92X RDO: Factory RDO configuration.