The Daniel Defense DD4 MK18 RIII is a purpose-built 5.56 NATO short-barrel rifle designed for shooters who need a compact, maneuverable platform without sacrificing capability. With its 10.3" cold hammer forged barrel, this SBR delivers the handling characteristics of a carbine in a footprint suited to vehicles, tight quarters, and dynamic shooting scenarios. Whether you're setting up a truck gun, training at distance, or running drills on a closed course, the MK18 RIII combines Daniel Defense's proven upper and lower receiver engineering with features that just work.
The rifle ships with an ambidextrous lower receiver, giving you safety controls and magazine release accessible from either side—essential if you shoot southpaw or need flexibility in your grip. Daniel Defense's own ergonomic grip and stock keep your hand placement natural and your sight picture stable. The included 32-round magazine gives you practical capacity without requiring specialized sourcing, and the manual safety is straightforward and reliable.
Daniel Defense's cold hammer forged barrel is cut to length specifically for this platform, balancing velocity and ballistics against the compact form factor. If you're comparing short-barrel rifles for versatility, the MK18 RIII is an honest choice: it does what it's designed to do, built by a maker with a reputation for consistency and customer support. This is a rifle you can train with, trust, and configure to your needs over time.
| Caliber | 5.56 NATO / .223 Remington |
| Barrel Length | 10.3" |
| Barrel Type | Cold Hammer Forged |
| Configuration | Short-Barrel Rifle (SBR) |
| Receiver Type | Ambidextrous Lower |
| Grip | Daniel Defense Proprietary |
| Stock | Daniel Defense Proprietary |
| Magazine Capacity | 32 rounds |
| Safety Type | Manual, Ambidextrous |
| Finish | Black Anodized |
It fires 5.56 NATO and .223 Remington ammunition. Both cartridges are widely available and suitable for training, medium-range shooting, and field use.
Yes. The ambidextrous lower receiver includes controls on both sides, making it comfortable and practical for southpaw shooters to operate the safety and magazine release without modification.
One 32-round Daniel Defense magazine is included, giving you a standard capacity option out of the box.
Short-barrel rifles like the MK18 RIII have barrels under 16 inches, making them more compact and maneuverable. The 10.3" barrel on this model reduces overall length while maintaining reliable 5.56 NATO performance for closer-range and vehicle-based use.
Firearm Shipments:
To buy rifles or shotguns, you must be 18 years old, and for handguns, actions, or receivers, the minimum age is 21. By placing an order for this firearm, you confirm that you are the legitimate transferee/buyer, meet the legal age requirements, and comply with all Federal, State, and local laws and regulations necessary to purchase this firearm.
We only ship firearms to valid Federal Firearms License (FFL) holders. At checkout we provide a FFL locator for your convenience.
We will need a copy of the FFL’s license to facilitate the process, kindly request your dealer to email us a copy of their FFL, as we cannot dispatch the firearm until we receive this document. It is imperative for the buyer to choose their FFL dealer, ensure they are willing to facilitate the transfer, and have them email their FFL copy to BOSQUE Outdoors. To avoid any confusion, the customer's name or order number must be mentioned in the email containing the FFL.
Email: [email protected]
Daniel Defense
Daniel Defense
Daniel Defense
