AK-47 Family

Steyr Aug / MSAR STG-556

Model-1 Sales .300 / 221 Fireball

Colt/Walther M4 .22 Carbine

Steyr Aug / MSAR STG-556

Here it is - a reasonably priced suppressor mount for your Steyr or MSAR!
Whether you are fortunate enough to own a real Steyr, or have purchased one of the slick new MSAR STG-556's - you now have an option to mount muzzle accessories. Like all of our mounts, these are CNC-machined on a Swiss-style lathe in one chucking to ensure concentricity.

These replace your current flash hider and adapt the M13 X 1.0mm LH threads to either 1/2 X 28 for 5.56mm accessories - or 5/8 X 24 for 7.62mm accessories. The reason for providing both options is to allow users that only own one 7.62 suppressor to use it on their AUG/STG. Not everyone owns a can for every caliber, so we provide the option to use what you have with your rifle, 7.62 suppressors work surprisingly well on 5.56mm weapons.








Click here to see video of a MSAR STG-556 with a Gemtech HVT suppressor mounted via Halcyon Defense adapter

    MSAR STG-556 with 5/8 X 24 adapter mounted  MSAR STG-556 with Gemtech HVT out at the range


FREE SHIPPING to the continental US!

$30.00 USD 1/2 X 28 AUG/MSAR Thread Adapter
for use with 5.56 mm accessories and sound suppressors
$30.00 USD 5/8 X 24 AUG/MSAR Thread adapter
for use with 7.62 mm accessories and sound suppressors


By purchasing Halcyon Defense thread adapters, I acknowledge that: Halcyon Defense produces precision thread adapters that are held to the most stringent quality control standards possible. The end user of Halcyon Defense products is responsible for ensuring that barrels, suppressors, and all other devices that Halcyon Defense thread adapters may be utilized with have threads that are concentric to the bore, and that any projectile that passes through these devices will do so without striking any component in the weapon system. Some manufactures do not adhere to the same standards and precise tolerances as Halcyon Defense, and Halcyon De mage to any component that occurs while using Halcyon Defense thread adapters.