IRREGULAR DESIGN GROUP HESYCHIA 556UK

The Irregular Defense Hesychia 556UK is a purpose-built 5.56 NATO duty suppressor engineered for shooters who demand maximum durability, minimal added length, and reliable performance under hard use. Built from Inconel 718 and weighing just 13 ounces, the 556UK delivers exceptional sound suppression, flash reduction, and low back pressure in an ultra-compact package without requiring rifle modifications or tuning.

At the heart of the Hesychia 556UK is Irregular Defense's advanced Hybrid Core gas management architecture, which controls pressure from the earliest stages of the firing cycle rather than simply trapping gas inside the suppressor. This results in reduced gas blowback, improved shooter comfort, and reliable cycling across a wide variety of rifle platforms.

The innovative Hesion Bow Lock System provides a secure, repeatable mounting solution utilizing six integrated flexure pawls, a 15-degree taper interface, and a coarse 1-1/8"-8 left-hand American Buttress Thread. This redundant locking system ensures excellent alignment and retention, even during high-volume or full-auto firing schedules.

Designed around the Micro Flow Enhancer muzzle device, the Hesychia 556UK treats the muzzle device as an integral part of its gas management system rather than a simple mounting accessory. The result is outstanding flash suppression, reduced recoil impulse, and balanced performance without turning your rifle into a tuning project.

The suppressor features a fully welded monolithic construction with no removable baffles, making it exceptionally durable while requiring minimal maintenance. Rated for full-auto use on barrels as short as 10.3 inches, the Hesychia 556UK is an excellent choice for duty rifles, defensive carbines, and professional applications where reliability and compactness are essential.

Features

• Dedicated 5.56 NATO duty suppressor
• Ultra-compact design with minimal added length
• Manufactured from Inconel 718
• Fully welded monolithic construction
• Advanced Hybrid Core gas management architecture
• Low back pressure design
• Excellent flash suppression
• Hesion Bow Lock dual-lock mounting system
• Six integrated flexure locking pawls
• 15-degree taper locking interface
• 1-1/8"-8 left-hand American Buttress Thread
• Designed around the Micro Flow Enhancer muzzle device
• Full-auto rated
• No firearm tuning required
• Made for demanding duty and professional use

Specifications

• Manufacturer: Irregular Defense Group
• Model: Hesychia 556UK
• Caliber: 5.56 NATO
• Material: Inconel 718
• Finish: High Temperature Cerakote Armor Black (optional coatings available)
• Weight: 13 oz
• Overall Length: 4.75"
• Construction: Fully Welded Monolithic Core
• Mounting System: Hesion Bow Lock
• Primary Lock: 15° Taper
• Thread Interface: 1-1/8"-8 Left-Hand American Buttress Thread
• Locking System: Six Integrated Flexure Pawls
• Muzzle Device: Micro Flow Enhancer (sold separately or available as bundle)
• Minimum Barrel Length: 10.3"
• Full Auto Rated: Yes
• Design: Low Back Pressure Hybrid Core
• User Serviceable: No
• Installation Torque: 30 ft-lbs (Muzzle Device)
• Recommended Break-In: 5-7 mount/removal cycles
• Threadlocker Required: No (under normal installation)