Irregular Design GroupHesychia SIXK
6mm / 6.5mm suppressor · IDG Hesion Bow interface · specs and compatibility from the manufacturer
Notable features
- Low Backpressure
- Full-Auto Rated
- Sealed
length
5.72″
weight
15.5oz
MSRP
$1,195
length
5.72″
weight
15.5oz
calibers
5.56 | 6.5
material
Inconel
interface
IDG Hesion Bow
MSRP
$1,195
- Overall length
- 5.72″
- Diameter
- 1.65″
- Weight
- 15.5 oz
- Class
- 6mm / 6.5mm
- n
- 98
- Range
- 4.4 oz–23.9 oz
- Median
- 12.45 oz
- Material
- Inconel 718
- Max caliber
- 6mm ARC
- Base interface
- IDG Hesion Bow
- Front cap
- Fixed
- Backpressure
- Low
- Full-auto rated
- Yes
- Barrel restriction
- 10.3" minimum
- Maintenance
- Sealed (not user serviceable)
- MSRP
- $1,195
- Class
- 6mm / 6.5mm
- n
- 86
- Range
- $260–$1,529
- Median
- $975
Heavier than most 6mm / 6.5mm suppressors
Weight compared against the 98 6mm / 6.5mm suppressors in the catalog that publish one. Quartile basis; a value inside the middle half carries no note.
Pricier than most 6mm / 6.5mm suppressors
MSRP compared against the 86 6mm / 6.5mm suppressors in the catalog that publish one. Quartile basis; a value inside the middle half carries no note.
Prices are manufacturer's suggested retail (MSRP). What you pay may differ.
- Base interface
- IDG Hesion Bow
- Front cap
- Fixed
This suppressor's IDG Hesion Bow takes no separate mount. 6 muzzle devices in our catalog attach to it directly.
Which ones fit your barrel and host?
Check in the BuilderManufacturer claim
- The SIXK is full auto rated, with an extreme low backpressure gas profile.
- Irregular Design Group measures the SIXK at 139 dB at the ear and 143 dB at the muzzle on a DD MK18 10.3 test platform.
- Irregular Design Group designed the system so it does not need any tuning for any firearm host it mounts to — no adjustable gas blocks, heavier buffers, or different springs required to make the suppressor work.
- Flexure pawls are printed within the suppressor body under protective hoods to provide six bi-directional indexing arms that engage within 32 grooves around the outer edge of the muzzle device, adding only .5 oz. to the entire system.
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- The primary lock is a 15-degree taper over 0.25" of length paired with a 1 1/8"-8 left-hand American Buttress Thread. Just 15 ft./lbs. of torque generates over 1,700 lbs. of sealing force, and full taper lock takes less than 2.5 rotations.
- The SIXK adds 3.6" of length to the muzzle device, in a 5.72" overall length at 1.65" diameter.
- Gas enters a radial diamond structure in the initial chamber, gets disrupted and cooled, then gets pulled into annular pathways early, before the first blast baffle has a chance to become a pressure traffic jam.
- The SIXK is a monolithic Inconel 718 body produced by Laser Powder Bed Fusion (LPBF), with the critical interfaces machined afterward.
- Inconel 718 is the material choice because it holds its shape, resists erosion, and survives thermal cycling. It is not the lightest option and not the cheapest option.
- The blast baffle receives a dedicated treatment to harden that zone against premature blast baffle erosion.
- The SIXK is a sealed monolithic unit. There are no user-serviceable internal components and no baffles to remove individually.
- Compatible muzzle devices are the Hybrid Flash Hider, the Micro Flow Enhancer and the Macro Flow Enhancer.
- Install the muzzle device to the barrel at 30 ft./lbs. Timing is not required for the HFH or Flow Enhancers, and threadlocker is not normally required under standard installation.
- New systems should be mounted, seated, removed, and repeated for roughly 5 to 7 cycles so the interfaces settle, followed by a short validation firing sequence.
- The SIXK is full auto rated for 10.3" barrels and above. The minimum recommended barrel length for the 5.56 and 6mm rifle suppressors in this system is 10.3", and going shorter increases blast baffle erosion and raises projectile stability risk.