SilencerCo® Bravo/Osprey/Octane Extended Booster Piston – 1/2x28 XL – Heat-Treated Stainless Steel – AC59
The SilencerCo® Extended Booster Piston (1/2x28 XL) (AC59) is a premium, heavy-duty suppressor optimization component engineered to facilitate flawless semi-automatic mechanical cycling on handguns with specialized barrel geometries. While standard booster pistons function perfectly on traditional factory-threaded barrels, they fall short when pairing a suppressor with pistols that feature exceptionally long thread shoulders, extended slides, or deeply recessed target crowns—such as select Beretta® models or custom tactical builds. Firing these setups with a standard piston risks binding the suppressor chassis directly against the slide face, resulting in failure-to-cycle stovepipes or catastrophic frame damage. The SilencerCo XL Piston (817272010237) masterfully eliminates this barrier, adding an extra 0.25 inches of structural clearance between the rear of the suppressor and the front of the firearm's slide.
Precision CNC-machined from high-strength, premium 17-4 stainless steel and finished in a slick, carbon-resistant treatment, this rugged piston is heat-treated to maximum hardness thresholds to withstand extreme abrasive wear, blast pressures, and rapid thermal cycling. Functioning as a foundational link in your silencer's internal Nielsen device (booster system), the AC59 isolates the weight of the suppressor from the host pistol barrel, allowing tilting-barrel handguns to cycle flawlessly without manual assistance. The female 1/2x28 XL thread pitch screws securely onto matching muzzle threads, maintaining dead-center concentric alignment to prevent dangerous baffle strikes. Universally interchangeable across a broad segment of the SilencerCo product catalog, this 1.92-ounce mechanical asset can also be adapted to fixed-barrel carbines or sub-guns simply by swapping out the booster spring for a companion fixed barrel spacer, giving hunters, tactical marksmen, and military operators total modularity across their armory layouts.
Includes: (1) SilencerCo Extended Suppressor Booster Piston with 1/2x28 XL Female Thread Pattern (Matte Finish).
*Application & Safety Note: This is an extended "XL" variant that adds an additional 0.25 inches of overall clearance compared to a standard AC25 piston. It is natively rated for 9mm Luger and smaller centerfire cartridges. Never operate a booster spring assembly on a fixed, non-tilting barrel rifle or rimfire weapon without replacing the internal spring with a solid spacer, as doing so can damage your receiver extension threads.
Key Features
- Extended 0.25" XL Clearance Profile: Explicitly designed to provide essential spacing between the suppressor rear cap and pistol slide face, opening up compatibility for long-shoulder custom barrels.
- Hardened 17-4 Stainless Steel Core: Heat-treated structural steel build withstands thousands of rapid semi-automatic combustion cycles, resisting gas erosion and thread scaling.
- Nielsen Device Optimized Cycling: Seamlessly drops into factory spring booster housings, neutralizing silencer weight to enable rapid, malfunction-free slide cycling.
- Precision 1/2x28 TPI Concentricity: Clean, CNC-cut internal threads register perfectly square against your barrel shoulder to protect alignment and prevent dangerous baffle strikes.
- Dual-Platform Adaptability: Runs natively as a spring-assisted booster on handguns, or converts into a rigid direct-thread hub for sub-guns when paired with a fixed barrel spacer.
- Genuine West Valley Factory Original: Authentic SilencerCo OEM accessory pack guarantees exact dimensional tolerances to protect your high-end NFA investment warranties.
Product Specifications
- Brand: SilencerCo®
- Product Line: Suppressor Interface Booster Pistons
- Model Name: Piston 1/2x28 XL
- SKU / MPN: AC59 (Alternative Part Reference: SCO-AC59)
- Thread Pattern Interface: 1/2"x28 TPI Extended (1/2x28 XL) Female
- Caliber Accommodation: 9mm Luger / .357 SIG / .300 Blackout (Subsonic) & Smaller
- Chassis Core Composition: Heat-Treated 17-4 Stainless Steel
- Colorway / Finish: Industrial Matte Black / Stainless Dark Treatment
- Piston Variant Class: Extended Length (+0.25 Inches over Standard)
- Suppressor Compatibility: Osprey Series, Octane Series, Omega K Series, Hybrid 46
- Modular System Compatibility: Omega 36M & Hybrid 46M (with Charlie Piston Mount installed)
- Primary Application: Restoring Semi-Auto Cycling to Extended-Shoulder / Long-Slide Handguns
- Country of Origin: Proudly Made in the USA (West Valley City, Utah)
- Product Net Weight: ~1.92 oz (54.4 g)
- UPC: 817272010237
