Due to the demand and dedication we put into every order, please allow 4-6 weeks for SIEGE to ship your suppressor. We promise it will be worth the wait!
This is an NFA item and it must be transferred to your preferred FFL & SOT. Please email the FFL & SOT you would like to use for transfer along with your order number to: info@siegesuppressors.com
ABOUT THE ROC556K:
The ROC556K by Siege Suppressors uses Linear Diffuser Array technology.
Video - What happens inside of the Linear Diffuser Array? https://www.youtube.com/watch?v=II-aLNxDYxc
The linear diffuser array is engineered to redirect propellant gasses radially through an arrangement of turbulent and laminar flow cells. Each series of cells flows into the next until propellant, lead, copper, and carbon are expelled at the exit. The internal geometries greatly reduce the potential for long-term build-up or fouling. It is by design, self-cleaning
The same design mechanism that promotes the free flow of gasses from cell to cell also diminishes back pressure significantly. The large surface area and the unique diffuser geometries effectively reduce the sound and flash signature without the excessive blowback experienced with more common designs.
Reducing excess back pressure removes a major cause of over-pressure-induced failures and maintains the host weapon's inherent reliability. An added benefit of a low back pressure design is an improved shooter experience with less gas presented to the shooter’s face when using AR and bullpup-type weapons.
Siege Suppressors also offer extreme durability and erosion resistance due to the design of the diffuser array, monolithic structure, and contiguous bore. Siege suppressors are designed to use a contiguous bore within the linear diffuser array, different from any other suppressor. The contiguous bore is a design feature that offers increased erosion resistance compared to conventional designs due to the flow characteristics of propellant gasses and unburned gunpowder through the suppressor. Because there are no angular features and no baffles used in the internal construction of the suppressor, the propellant gasses and unburned gunpowder have no angular barriers to react against and therefore erode over time.
In a Siege Suppressor, propellant gasses and unburnt gunpowder travel around the diffuser array, down the contiguous bore, and out of the muzzle end of the suppressor. The unique flow of gasses within a Siege Suppressor provides a suppressor that is less prone to internal erosion from propellant gasses and unburnt gunpowder when compared to traditional baffled suppressor designs.
SPECS:
Caliber: 5.56mm
Length w/ STRONGHOLD adapter: 5.68"
Length w/o mount: 5.18"
Diameter: 1.5”
Weight w/ STRONGHOLD adapter: 14.68oz
Weight w/o adapter: 12.78oz
Materials: Precipitation Hardening SS & Inconel Linear Diffuser Array
Finish: Nitride
Full Auto Rated
No Barrel Length Restrictions
WHATS IN THE BOX:
ROC556K Suppressor
2 - Siege Spanner wrenches
Siege STRONGHOLD HUB Adapter & DEFENDER 2 Port Brake 1/2x28 - Plan B Compatible
5.56mm vented removable endcap
1 reviews for ROC556K - Includes: STRONGHOLD HUB Adapter & DEFENDER 2 Port Muzzle Brake
Wyatt
Jul 06, 2025Ive come to the full conclusion as a very early adopter of the ROC556K that this thing is just flat out filled full of black magic. It feels LESS gassy than unsuppressed, sounds amazing considering its a K-can. Gives me everything I hoped for and more. Makes shooting so much nicer and pleasant. -Quality fit and finish -Looks SUPER SWEET -Good weight and with mount and hub balances out my 16" AR-15 very well. -Mount and hub are very well built -Nothing on this thing is going to get stuck on your rifle or leave you in a pickle, every part from the suppressor/muzzle device/hub with the included wrenches has points to grab onto and leverage. -The endcap is probably one of the coolest in the industry and isnt all for show. It very clearly does a LOT to help gas flow through and keep it away from the chamber. All in all if youre looking for a short can that has great performance, low profile, and extremely low back pressure this is probably what would fit perfectly. They really left no stone un-turned and thought of every single aspect of this during design. I cant find anything Id change or any design flaws. It feels like an extremely premium product down to even the impressively designed packaging. I wasnt paid to post this, I bought this with my own money and waited like everyone else. I didnt receive any non-public discounts either.
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