HDA3 Stock/Brace for CZ Scorpion

Product Description

The HDA3 is a modular stock/brace system developed from a collaboration between Haga Defense and A3 Industries. The HDA3 was designed specifically to integrate seamlessly across dozens of firearm platforms without sacrificing strength or aesthetics to do so. 

The HDA3 fills a footprint that the gun industry has already come to love while providing a level of quality, modularity and durability that has never been offered in a similar package. The HDA3 is designed, manufactured and assembled in the USA. 

FEATURES:

• Folding Steel Hinge: The HDA3 utilizes a steel hinge assembly, ensuring a strong lockup in the straight and folded position that will not degrade with use. The HDA3 will by default fold to the left side canted at 3.5 degrees. Right side folding variants will be available at a later date. 
• Strong Bones: The HDA3 is designed with all metal internal components for maximum durability. An aluminum cheek riser button and length adjustment latch both interface with an extruded aluminum spine that ties into the steel hinge. 
• Stock & Brace Configurations: The HDA3 is available as a stock with an injection molded extension and rubber buttpad or as a brace with an injection molded extension designed to accept a variety of arm braces. See below for brace compatibility. 
• Adjustment: The HDA3's length can be adjusted in .5" increments between 7 positions. The cheek riser can be used in three positions. In the lowered position, raised .25" or raised .5". Both adjustments can easily be manipulated one-handed. 

SPECIFICATIONS:

• Mounts directly to the CZ Scorpion (all variants)
• 6061 hardcoat anodized aluminum adapter
• Adapter dimensions: 2.5" Tall by 1.74" Wide
• Built-in tension adjustment for wobble free fit
• Length:
• Stock configuration: 7.9-10.9"
• Brace configuration (without brace): 8.2-11.2"
• Weight:
• Stock configuration: 1lb 3.3oz
• Brace configuration (without brace): 1lb 1.9oz
• Heavy duty Locking Hinge
• Nitride coated 17-4 stainless steel
• Folds to the left side canted at 3.5 degrees
• 7 Position extrusion with length adjustment in .5" increments
• 6061 aluminum extrusion with 7075 aluminum locking latch. Hardcoat anodized
• 3 Position Cheek Riser (0, +0.25" & +0.50")
• Polymer construction with hardcoat anodized 6061 aluminum adjustment button
• Textured Butt-pad (stock) manufactured from injection molded "rubber-like" Santoprene TPE
• High-Strength Polymer: All polymer components are injection molded 30% glass fiber reinforced nylon. 
• Sling Mounts: There is a sling loop as well as two steel QD mounting points at the rear of the HDA3. There are three additional QD mounts machined into the aluminum adapter. 
• Color: Available in Black, FDE, ODG and Gray. 
• Designed, manufactured and assembled in the USA

PISTOL BRACE CONFIGURATION:
When purchasing the pistol brace configuration the HDA3 will be shipped with a brace mount not a butt-pad.  The brace mount will accept tube mount style (1.195" Dia.) pistol braces which are NOT included.

Braces that are compatible with the HDA3 are listed below and can be purchased separately

• A3 Steady Brace (click here)
• Gear Head Works Tailhook MOD1 (click here)
• Gear Head Works Tailhook MOD1C (click here)
• Midwest Ind. Arm Brace Hook - modification required (click here) 

DISCLAIMERS: Customer is responsible for being aware of local, state, and federal laws regarding the use of this product.

ADJUSTABLE CHEEK RISER

LOCKING STEEL HINGE

ADJUSTABLE LENGTH

PISTOL BRACE VARIANT

BUILT-IN QD SLING MOUNTS

RUBBER BUTTPAD

OPERATION (VIDEO)

INSTALLATION:
1. Physically and visually check that the firearm is unloaded and that the magazine and ammo have been removed.

2. To remove your old stock, brace or backplate you will need to press in and hold on a detent in the back of the receiver while lifting the stock, brace or backplate up and off of the firearm. There will be an access hole in your stock/brace adapter or backplate that you can push a small punch through to access the detent. 

3. Slide on the HDA3 Stock or Brace the same way the old part came off. Once it reaches the detent you may need to press in on it (the detent) with your finger until the HDA3 slides all the way on. You will hear the detent click into place when HDA3 has been fully installed. 

4. Because of variations in receivers the HDA3 may "wiggle" when installed on some Scorpions. The HDA3 has a built-in feature to eliminate this loose fit. If you have some play in your fit locate the nylon set screw circled below and using a 3/32 hex wrench carefully tighten it until you have a wiggle free fit. Be very careful not to overtighten the set screw as it can easily be damaged. Nylon set screws are used to prevent any damage to the Scorpion receiver.

5. To remove the HDA3 stock or brace use a small punch as pictured below to press in the detent on the receiver and release the HDA3.