Flux Defense Raider X-Chassis SIG Sauer P320 9mm Luger, Compact 3.9-in Barrel, 21+1 rd, Spring-Loaded Side-Folding Brace
This custom SIG Sauer P320 fire-control unit is factory-installed in the Flux Defense Raider X chassis, turning a proven striker-fired compact pistol into a fast-deploying personal-defense weapon. The spring-loaded side-folding brace extends in under half a second, while the integrated spare-magazine cradle boosts on-gun capacity to 42 rounds. Clean, modular, and ready for accessories, this Raider X build offers PDW performance without giving up P320 versatility.
Condition
Overall Condition: Excellent condition, showing only faint signs of any prior use or handling.
Bore Condition: Excellent – Clean, mirror finish, no signs of wear.
Bore Rifling: Excellent – Sharp lands and grooves.
Specific Condition Notes: Only light handling marks on high-contact chassis surfaces; no functional or cosmetic issues observed.
What’s Included
- Flux Defense Raider X P320 spring-loaded brace chassis (installed)
- SIG Sauer OEM P320 Carry polymer grip module
- 2 × 21-round steel magazines with aluminum +4 basepads
- 2 × 17-round steel magazines with orange followers
The heart of this package is the modular P320 fire-control unit, allowing the user to revert between a standard pistol and the braced Raider X PDW configuration without tools. A full-length Picatinny top rail and molded M1913 side rail slots give ample real estate for optics, lights, or lasers.
The Raider X brace deploys via a captured spring—press the release and it snaps to a locked, shoulder-stable position in under 0.5 seconds. When folded, overall length is approximately 15.5 inches, making storage and transport simple; deployed length is roughly 22 inches.
An integrated spare-magazine well sits just behind the trigger guard, holding an included 21-round magazine with +4 aluminum basepad. Coupled with the primary 21-round magazine, the system carries 42 rounds on the gun before any reloads.
The compact 3.9-inch carbon-steel barrel, matte-black slide with front and rear serrations, and polymer carry-length grip module keep weight to 40–42 ounces empty. Standard 3-dot iron sights—with a white-dot front blade—offer a familiar sight picture, while the striker-fired action retains the crisp P320 trigger pull.