SIG SAUER M400 DH3 Competition Rifle RM400SDI16BDH3 — Description

The SIG SAUER M400 DH3 Competition Rifle RM400SDI16BDH3 is a high-performance .223 Wylde semi-automatic rifle developed in collaboration with championship 3-Gun competitor Daniel Horner. Designed specifically for competition performance, the M400 DH3 combines SIG Sauer’s M400 SDI platform with premium upgrades including a DH3 fully adjustable competition stock, Timney two-stage Daniel Horner signature trigger, and a precision 16-inch fluted stainless steel barrel.

The rifle features a Cerakote Elite Titanium finish, lightweight aluminum receiver, low-profile competition handguard with M-LOK attachment points, and fully ambidextrous controls. The .223 Wylde chamber is optimized to support both .223 Remington and 5.56 NATO ammunition, providing versatility for competition and range use.

Built around a direct-impingement operating system, the M400 DH3 includes a three-chamber compensator designed to reduce muzzle movement during rapid fire, along with a competition-focused trigger and adjustable stock setup that allow shooters to fine-tune the rifle to their preferred shooting style.

SIG SAUER M400 DH3 Competition Rifle RM400SDI16BDH3 — Specifications

Manufacturer: SIG SAUER
Model: M400 DH3 Competition Rifle
Model Number: RM400SDI16BDH3
Caliber: .223 Wylde (accepts .223 Remington / 5.56 NATO)
Action: Semi-automatic
Operating System: Direct gas impingement with rotary bolt
Platform: AR-15 style rifle

Barrel Length: 16 inches
Barrel Material: Fluted stainless steel
Barrel Twist Rate: 1:8″
Chamber: .223 Wylde
Receiver Material: Aluminum
Finish: Cerakote Elite Titanium finish
Handguard: Low-profile competition M-LOK handguard
Stock: DH3 fully adjustable competition stock
Trigger: Timney two-stage adjustable Daniel Horner signature trigger
Magazine Type: AR-15 / STANAG compatible magazine
Magazine Capacity: 30 rounds
Muzzle Device: Three-chamber compensator
Controls: Fully ambidextrous controls
Rail System: Full-length Picatinny top rail
Overall Length: Approx. 34.5 inches
Weight: Approx. 7 lbs

Key Features

• Daniel Horner DH3 competition configuration
• .223 Wylde chamber for .223 Remington and 5.56 NATO compatibility
• 16-inch fluted stainless steel barrel
• Cerakote Elite Titanium finish
• DH3 adjustable competition stock
• Timney two-stage adjustable DH3 trigger
• Three-chamber compensator for recoil control
• Low-profile M-LOK competition handguard
• Fully ambidextrous controls
• Free-floating barrel design
• 30-round magazine included
• Built for 3-Gun and competitive shooting performance

Package typically includes:

• SIG SAUER M400 DH3 Competition Rifle
• 30-round magazine
• DH3 adjustable stock
• Timney DH3 two-stage trigger
• M-LOK competition handguard
• Owner’s manual and safety documentation