Strike Industries FSA Stabilizer Stock Picatinny Edition - Fits 1913 Picatinny Rail End Plates - Folding Mechanism, Length of Pull Extension Adjustments - Matte Black Polymer - SI-FSA-SP-STOCK
Product Description
If you are building a modern compact rifle or a sub-gun style platform, using standard AR-15 buffer tubes and fixed stocks can make your setup unnecessarily bulky. Traditional receiver extensions limit how small you can pack your weapon for storage or vehicle carry. The **Strike Industries® FSA Stabilizer Stock Picatinny Edition (SI-FSA-SP-STOCK)** is custom-engineered to solve this bottleneck. It lands on your armorer bench as a fully complete, dual-function folding stock conversion system built to mount straight onto platforms utilizing a rear 1913 Picatinny rail interface.
Proudly engineered to deliver modular versatility, this package features a high-strength folding hinge mechanism precision-machined from 6061-T6 aluminum and treated with a hardcoat anodized layer. Attached to the hinge is a rigid, lightweight stock shell molded from a high-impact, glass-filled polymer matrix that handles drop shocks and rough transit with ease. The **FSA Stabilizer Stock** configuration gives you an adjustable length of pull (LOP) tracking channel with multiple extension settings, letting you customize your shoulder fitment right on the bench. When you need a ultra-compact footprint, the intuitive lift-to-unlock hinge allows you to fold the entire stock flat against the side of your receiver block.
The stock profile features a rubberized non-slip butt pad, built-in QD sling swivel sockets on both sides, and clean structural geometries that clear your ejection port while folded. It is the ultimate asset for tricking out your MCX, MPX, CZ Scorpion, or custom 1913 railed receiver layout.
*Armorer Bench Notes & Real-World Staging Guidance: The Strike Industries SI-FSA-SP-STOCK arrives fully complete and factory-packaged with all required cross-bolt fasteners and hex tools organized inside its box. UNIVERSAL 1913 PICATINNY RAIL FITMENT DIRECTIVE: This stock system is engineered natively to clamp onto a rear-facing vertical mil-spec 1913 Picatinny rail section. It is a direct drop-in match for platforms like the Sig Sauer® MCX/MPX series, CZ® Scorpion EVO 3 (with Picatinny backplate), Ruger® LC Carbine, and AR-15 frames fitted with a Picatinny stock adapter. CRITICAL LEGAL COMPLIANCE MATRIX: This product is factory-configured as a Rifle Stock Assembly featuring a solid structural rear butt pad footprint. Installing this component onto a handgun configuration (a firearm built with a bare pistol lower receiver and a barrel length under 16 inches) converts it into a "Short-Barreled Rifle" (SBR) under federal guidelines. Ensure your firearm setup complies with all NFA tracking, tax stamp regulations, and local jurisdiction rules on your bench before tightening the hardware downrange. Armorer Workbench Hinge Orientation Tuning: This advanced hinge is fully ambidextrous and can be configured to fold to either the left or right side of your receiver. Out of the box, it is set to fold to the left. If your receiver setup features left-side charging handles or bolt locks, you can easily reverse the layout by flipping the internal hinge mechanism upside down on your bench during assembly. Torque Parameter Guidelines: When clamping the steel mounting block onto your rear Picatinny rail slots, torque the primary hex clamping bolts to exactly **25 to 30 in-lbs**. Apply a single drop of medium blue threadlocker to the fastener rows to freeze the mount against live-fire vibrations; avoid over-tightening past factory parameters to protect the aluminum clamping teeth from warping downrange.*
Key Features
- Direct 1913 Picatinny Clamping: Mounts securely onto any vertical rear-facing Picatinny rail end plate, cutting out the need for conventional AR buffer tubes.
- Ambidextrous Folding Mechanism: Heavy-duty lift-to-unlock aluminum hinge can be easily set up to fold to the left or right side based on your weapon layout.
- Adjustable Length of Pull: Features a modular tracking channel with multiple extension lock slots to customize your overall shoulder length comfortably.
- Glass-Filled Polymer Stock Shell: Molded from a high-impact, weather-proof composite matrix that keeps weight down while maximizing structural stiffness.
- Integrated Dual QD Sling Ports: Outfitted with built-in quick-detach sling swivel sockets on both sides to support fast tactical sling tracking transitions.
- Clears Ports While Folded: Designed with a streamlined, low-profile frame contour that won't block the ejection port or trigger guard when folded flat.
Product Specifications
- Brand: Strike Industries® (Las Vegas, Nevada)
- Model Line: FSA (Folding Stock Adapter) Stabilizer Custom Long-Gun Series
- MPN/SKU: SI-FSA-SP-STOCK (Also cataloged as SI-FSA-SP-STK-BK)
- UPC Code Profile: 793811767971
- Mount Interface Standard: Mil-Spec 1913 Vertical Picatinny Rail (Rear Interface Spec)
- Hinge Component Material: High-Tensile CNC-Machined 6061-T6 Aircraft-Grade Aluminum
- Stock Body Construction: Advanced High-Strength Glass-Reinforced Polymer Matrix
- Exterior Finish Dressing: Non-Reflective Tactical Matte Black Core Textured Finish
- Folding Operation Style: Mechanical Lift-to-Unlock Tension Pivot Hinge (Ambidextrous Reversible)
- Length of Pull Range: Multi-Position Adjustable Extension Lock Slots
- Sling Attachment Framework: 2x Integrated Ambidextrous Quick-Detach (QD) Sling Swivel Ports
- Butt Pad Surface Style: Molded Slip-Resistant Rubberized Shoulder Traction Pad
- Compatible Firearm Families: Sig Sauer® MCX / MPX, CZ® Scorpion, Custom AR-15 Picatinny Builds
- Full Kit Component Checklist: FSA Folding Hinge Base, Adjustable Polymer Stock Sub-Assembly, Picatinny Clamping Blocks Pack, High-Tensile Steel Fasteners, Installation Allen Keys
- Packaging Format Class: Strike Industries Branded Factory Retail Presentation Box
- Product Type Category: Firearm Components / Rifle Buttstocks & Folding Adapters
- Overall Unit Folded Width: Minimalist Low-Profile Frame Extension Silhouette
- Net Component Module Mass: ~14.60 Ounces (Lightweight Heavy-Duty Solid-State Alloy & Polymer Core)
- Country of Manufacture: Proudly Designed and Engineered in the United States of America
- Warranty Tracking Protection: Fully Backed by Strike Industries Factory Parts Guarantee
