Daniel Defense 10.3″ Cold Hammer Forged Barrel, 5.56 NATO, 1:7 Twist, Government Profile, Carbine-Length, with Fixed Front Sight Base

Product Description

The Daniel Defense 10.3″ Cold Hammer Forged Barrel is a 5.56mm NATO, 1:7 twist, Government-profile barrel on a carbine-length gas system in the fixed front sight base configuration, and 10.3 inches is the length associated with the MK18 close-quarters pattern.

This is a short-barrel build barrel and nothing else. At 10.3 inches you are building either a registered short-barrelled rifle or an AR pistol; there is no configuration where this length becomes a standard rifle. What you buy for that compromise is a package that clears doorways, fits behind a vehicle seat, and puts almost no weight out front.

The Government profile keeps a useful amount of steel under the handguard, which matters on a short barrel where heat has nowhere to go. The fixed front sight base configuration pins the gas block and front sight tower together as one unit, giving a permanent front iron sight and the classic MK18 silhouette, at the cost of a long free-float handguard running over the block.

Key Facts

• Brand: Daniel Defense
• Model: 10.3″ 5.56mm, Carbine, 1:7, GOV
• Manufacturer Part Number: 07-077-02123
• Caliber: 5.56mm NATO
• Barrel Length: 10.3″
• Twist Rate: 1:7
• Barrel Profile: Government
• Gas System: Carbine Length
• Manufacturing Process: Cold Hammer Forged
• Material: 4150 Chrome Moly Vanadium (CMV) steel
• Bore Finish: Chrome lined
• Exterior Finish: Mil-Spec Heavy Phosphate
• Muzzle Thread: 1/2×28 TPI
• Diameter at Gas Port: .750″
• Barrel Extension: A4
• Barrel Weight (bare barrel): 1.15 lb
• Barrel Configuration: With front sight base (FSB)

NFA rules that apply to a 10.3-inch barrel

A barrel by itself is a component, not a firearm, so this barrel ships to you with no FFL transfer, no 4473 and no background check. The regulated moment comes at assembly. Installing a 10.3″ barrel on a rifle-configured receiver creates a short-barrelled rifle under the National Firearms Act, and that requires registration with BATFE, an approved transfer and a tax stamp. There is no muzzle device that makes 10.3 inches legal as a rifle. Western Sport is an SOT dealer, so the registered route can be handled here. If you are unsure which category your receiver falls into, call 817-393-4000 before you order.

10.3 versus 11.5 and 12.5 inches

Among short 5.56 barrels, 10.3 inches is the shortest of the three Daniel Defense carbine-gas Government-profile options and the one that trades the most velocity for the most compactness. Eleven and a half inches is the common middle ground and runs a little easier on gas. Twelve and a half gives noticeably better ballistics while still being much handier than a 14.5″ gun.

Compare all three short lengths in our Daniel Defense barrels, browse our MK18 products for MK18-pattern parts, and see what we stock in suppressors if this build is headed for a can.

Ordering from Western Sport in Roanoke, TX

Western Sport has held both an FFL and an SOT in Roanoke, Texas since 2007, and as a Daniel Defense master dealer with a gunsmith on site we build short guns regularly. Call 817-393-4000 and we will talk through the registration route or the pistol route before you spend a dollar.

Frequently Asked Questions

Q: Do I need a tax stamp to buy this 10.3″ barrel?

A: No. A barrel is a component, not a firearm, so it ships to you with no FFL transfer and no stamp. The stamp question arises when you assemble it. On a rifle-configured receiver a 10.3″ barrel makes a short-barrelled rifle, which must be registered with BATFE.

Q: Is 10.3 inches the MK18 barrel length?

A: Yes, 10.3 inches is the length associated with the MK18 close-quarters pattern, and this barrel pairs that length with a Government profile and a carbine-length gas system. Daniel Defense builds the same length into its own MK18 products. If you are cloning that configuration, this is the barrel length you want.

Q: Will a 10.3″ barrel cycle reliably with standard parts?

A: It can, but the length is demanding. A carbine gas system on 10.3 inches means high port pressure and a very short dwell, so buffer weight, spring rate and ammunition all matter more than they do on a 16-inch gun.

Q: How much does this barrel weigh?

A: Daniel Defense lists the barrel at 1.15 lb. That is the barrel itself; there is no published assembled figure for this length with the front sight base fitted, so we will not quote one. If you need the exact assembled weight for a build calculation, call 817-393-4000 and we will check.

Q: What muzzle thread does it use?

A: 1/2×28 TPI, the standard 5.56 AR-15 muzzle thread. That fits the usual range of flash hiders, brakes and suppressor mounts. Short barrels are hard on muzzle devices and very loud, so a device chosen for blast mitigation is worth considering.

Q: Can I run a full-length free-float handguard on this barrel?

A: Not with this configuration. The fixed front sight base pins the gas block and sight tower together above the barrel, so the handguard has to index against it or stop behind it. For a slim M-LOK tube that runs over the gas block on a 10.3″ build, choose the low profile gas block version of this barrel instead.

Additional information