HESYCHIA SIXK-H HUB

Designed by USSOF veterans, the Hesychia SIXK suppressor optimizes performance in the compact, under-six-inch category for 5.56mm NATO and 6mm ARC supersonic rounds. Through innovative gas management, monolithic Inconel 718 construction, and the patented Hesion Bow mounting system, it delivers effective sound and flash suppression, durability, and ease of use.

Design Philosophy

The Hesychia SIXK was engineered to overcome the limitations of K-series suppressors, which often struggle with sound suppression and low-backpressure balance for high-velocity 5.56mm and 6mm ARC rounds due to their compact size and lack of volume for managing excessive gas pressure. By prioritizing early gas control and high-flow dynamics, it achieves a balanced, durable system that minimizes audible and visible signatures without the need to add weight or length to achieve.

• Compact Performance: Delivers exceptional tone and sound suppression in a sub-six-inch envelope typical of K-series designs.

• Supersonic Optimization: Balances gas disruption and flow to prioritize a deep tone and low back pressure over total decibel reduction.

• Redundant Retention: The Hesion Bow system provides a positive locking taper with integrally redundant mechanisms to prevent the suppressor from coming loose from high firing schedules.

Gas Management System

The Hesychia SIXK employs a dual-path gas management system, splitting propellant gas into an external annular region and a central baffle stack to prolong off-gassing and reduce pressure fields, enhancing sound and flash suppression.

External Annular Region

The blast baffle captures initial gas, diverting it into an annular channel with eight sealed, variable-pitch helical chambers. Gas is redirected 180 degrees back toward the barrel, then spun down the suppressor’s axis into a final chamber, where shields enforce 90-degree turns to prevent direct venting.

• Blast Baffle Efficiency: Controls initial gas expansion to minimize rapid acceleration.

• Variable-Pitch Helix: Transitions from a loose to a tight twist, maximizing surface area and slowing gas via vectoring.

• Shielded Final Chamber: 90-degree redirects reduce pressure spikes, contributing to a lower tone than traditional low back pressure suppressors.

• Diamond-Patterned Blast Chamber: Doubles surface area for gas disruption and maximal abrasion resistance.

Annular Region Defined

An annular region is a ring shaped area bound by two concentric circles. It's essentially the area between the outer and inner circles, in this case, the outer shell and the inner core of the suppressor. This is a common technique employed by most additively manufactured suppressors in order to route excess blast chamber gas away from the central core, leaving lower pressure gasses to interact effectively with more abrupt disruptive geometries like baffles. While most suppressors leave this region vacant to encourage lower back pressure, the Hesychia SIXK does the opposite without increasing back pressure. If applied properly, gas that has been routed into the external annular region can be reintroduced back into the main core and exit out of the central bore without adding excessive pressure. This allows for a deeper tone and lower decibel levels than other suppressors that vent blast chamber gas directly to the atmosphere through the annular region.

Central Baffle Stack

Gas in the central bore flows through seven asymmetrical baffles, interlocked to maximize surface area and force differential volumes of gas diverting. A secondary bypass between baffles diverts gas into a deep, shielded chamber, balancing pressure during rapid fire while also reducing the amount of gas travelling down the central bore.

• Asymmetrical Baffles: Allow for a denser baffle core while also reducing the resonant gas stacking of symmetrically spaced and patterned baffles.

• Secondary Bypass: Bleeds gas into the final chamber at an angle to disrupt external annular gas entering from a different orientation.

• High-Flow Dynamics: Maintains performance under heavy firing schedules by avoiding gas accumulation through large ports. This also prolongs ports from clogging from carbon deposits between longer cleaning intervals.

Universal Host Platform

The Hesychia SIXK was designed to run on a wide range of host platform configurations and gas systems. From 10.3” barrel pistol length direct impingement gas systems to 16” short-stroke piston gas systems, the lack of additional backpressure from the suppressor removes the requirement for adjustable gas blocks for most platforms.

Flash Suppression

The Hesychia SIXK minimizes primary and secondary flash through internal gas combustion and a minimalist front-end geometry, preventing stoichiometric conditions that cause bright secondary flash.

• Internal Powder Burn: The final chamber’s large cavity and 90-degree gas mixing burn powder internally, reducing primary flash.

• Shielded Nose Cap: Three small slots with 90-degree shields vent gas laterally, minimizing secondary flash and excess pressure exiting the central bore.

• Low Back Pressure: Avoids large coaxial ports, reducing rapid atmospheric saturation for enhanced flash and sound control.

Material Selection and Manufacturing

Additively manufactured via laser powder bed fusion (LPBF), the Hesychia SIXK and its muzzle device use Inconel 718, ensuring durability and thermal stability under extreme conditions.

• Inconel 718: Maintains strength and dimensional stability at high temperatures, resisting thermal cycle fatigue.

• Fillet Corners: All internal edges radiused edges prevent stress concentrations, enhancing longevity.

• Camouflage Pattern Heat Sink: Outer surface of the suppressor has 3D camouflage impressions to increase surface area and thermal dissipation.

• Camouflage Pattern Weight Savings: This also is a weight saving technique that saves over 1.5 ounces from the total system weight, without negatively impacting the integrity of the outer casing.

• Monolithic Construction: LPBF enables complex geometries, such as the variable-pitch helix and diamond arrays.

Specifications

The Hesychia SIXK is a compact, lightweight suppressor designed for versatility and durability in demanding environments.