Search

GDM® 556 Rifle Suppressor

Balanced. Durable. Full-performance.

The GDM® 556 is the full-size suppressor in the GDM® 556 Series — designed for shooters who want maximum durability and effective 5.56 suppression without compromising reliability. Built from 17-4 stainless steel and 718 inconel and finished in DLC internally and externally, the 556 delivers consistent performance for high round-count use while maintaining universal mounting compatibility.

Why choose the GDM® 556?

  • Full-length design for improved suppression
  • 17-4 stainless steel and 718 inconel built for sustained firing schedules
  • Universal HUB interface (1.375×24)
  • DLC coating internally and externally for wear and corrosion resistance
  • Full-Auto and Force Reset Trigger (FRT) rated
  • Includes direct thread mount and wrench

Who the 556 is for:

General-purpose rifles | High round-count use | Duty & range builds

$899.99

Add to Cart
GDM® 556 Rifle Suppressor
$899.99
  • Made In the USA
  • NFA Compliant
  • Lifetime Defect Warranty

Compatible Accessories

NFA item. Compliance required. We assist throughout the process.

GDM® 556 Rifle Suppressor

The GDM® 556 is part of the GDM® 556 Series — a suppressor platform engineered specifically for 5.56 shooters who prioritize durability, sound reduction, and long-term reliability.

Manufactured entirely in-house at Guardian Defense Mfg’s family- and veteran-owned facility in Dayton, Ohio, the 556 is built for shooters running general-purpose or duty rifles where strength and consistency matter most.

At 6.5 inches long and 18.5 ounces, the GDM® 556 provides enhanced suppression over compact models while maintaining a manageable overall footprint. Its HUB (1.375×24) interface ensures compatibility with a wide range of industry-standard mounting systems, giving shooters flexibility without proprietary restrictions.

Independent third-party testing validates the performance of the GDM® 556 Series, ensuring objective data and real-world confidence.

Engineered for Durability & Performance

The GDM® 556 is constructed from 17-4 stainless steel and 718 inconel, offering exceptional strength and heat resistance for demanding firing schedules and extended use. A DLC coating internally and externally enhances surface hardness and corrosion resistance, making it well-suited for duty, training, and range environments.

The GDM® 556 Series is available in multiple configurations to support different mission profiles, with the full-size 556 optimized for shooters seeking a balanced combination of suppression and durability.

Universal HUB Mounting

The GDM® 556 features a 1.375×24 HUB mounting interface, providing compatibility with a wide range of popular mounting systems. This universal standard allows seamless integration into existing rifle setups without locking users into proprietary hardware.

  • Removable using the included wrench
  • Also includes 1/2 x 28 direct thread mount (additional size available for purchase)

Manufactured In-House

Every GDM® suppressor is:

  • Designed
  • Machined
  • Welded
  • Assembled
  • Packaged

In-house in Dayton, Ohio.

All GDM® suppressors are backed by a lifetime defect warranty, ensuring long-term confidence in your investment.

Additional information

Model Name

GDM® 556
Item Length

6.5 inches
Item Weight

18.5 oz
Item Diameter

1.612 inches
Material

17-4 Stainless Steel / 718 Inconel
Finish

DLC
Mount Interface

1.375 x 24 HUB
Caliber Rating

5.56 NATO / .223 Wylde
Included Components

1/2 x 28 Direct Thread, Suppressor, Wrench
Shipping Restrictions

Suppressors can only be shipped to an authorized FFL/SOT registered dealer. We cannot ship to the following states: CA, DC, DE, HI, IL, MA, NJ, NY, or RI.

Reviews

There are no reviews yet.

Only logged in customers who have purchased this product may leave a review.

Caliber Compatibility & Use Cases

Wondering if this suppressor supports your caliber or barrel length?

Use our caliber compatibility guide to confirm supported calibers, pressure considerations, and platform recommendations before shooting.

View Caliber Compatibility Guide

Compare the GDM® 556 Series

Choose the 5.56 suppressor that best matches your build, priorities, and shooting style.

FeatureGDM® 556KGDM® 556GDM® 556Ti
Length5.75"6.5"6.5"
Weight16.6 oz18.5 oz11.5 oz
Material17-4 Stainless Steel17-4 Stainless Steel & 718 InconelGrade 5 Titanium
FinishDLCDLCDLC
Durability FocusMaximumMaximumLightweight Performance
Mount InterfaceHUB (1.375×24)HUB (1.375×24)HUB (1.375×24)
Caliber Rating5.56 NATO / .223 Wylde5.56 NATO / .223 Wylde5.56 NATO / .223 Wylde
Supported PlatformsAR-15 • 5.56 carbines • SBRs • bolt-action 5.56 platformsAR-15 • 5.56 carbines • SBRs • bolt-action 5.56 platformsAR-15 • 5.56 carbines • SBRs • bolt-action 5.56 platforms
Ideal UseSBRs / Hard useDuty / General purposeCompetition / Lightweight builds
Balance PriorityCompactnessSuppression & durabilityWeight reduction
1/2 x 28 Direct Thread✓✓✓
Made In-House (USA)✓✓✓
Lifetime Defect Warranty✓✓✓

Which GDM® 5.56 Cal Suppressor Is Right for You?

Choose based on size, balance, and suppression priority.

GDM® 556K

Choose this if you want:

  • The shortest overall length
  • A suppressor optimized for SBRs
  • Maximum durability in a compact form

Best for:

SBRs • Hard-use rifles • Compact builds

View 556K

GDM® 556

Choose this if you want:

  • A full-size 5.56 suppressor
  • Balanced sound suppression & durability
  • A general-purpose duty option

Best for:

Duty rifles • General-purpose ARs • All-around use

View 556

GDM® 556Ti

Choose this if you want:

  • The lightest 5.56 option
  • Improved rifle balance
  • Reduced front-end weight

Best for:

Competition rifles • Lightweight builds • Balance-sensitive setups

View 556Ti

All GDM® suppressors are precision-manufactured in-house in the USA and backed by a lifetime defect warranty.

Need help choosing? Our team is happy to assist before or after purchase.

Suppressors are regulated items and must be transferred through an authorized Class 3 FFL / SOT dealer.

  • Suppressors cannot be shipped to a personal residence
  • Enter your selected FFL / SOT dealer’s address at checkout
  • Orders may be canceled if a residential address is entered

We do not ship suppressors to: CA, DC, DE, HI, IL, MA, NJ, NY, RI

Always verify caliber compatibility, barrel length requirements, and firing schedule limits before use. Improper use may result in damage, injury, or voided warranty.

Upgrade Your Setup

Related products