Daniel Defense 18″ Cold Hammer Forged Barrel, 5.56 NATO, 1:7 Twist, S2W Profile, Mid-Length, with Low Profile Gas Block

Product Description

The Daniel Defense 18″ Cold Hammer Forged Barrel, S2W profile, mid-length, with low profile gas block is a 5.56mm NATO, 1:7 twist heavy barrel in the low profile gas block configuration, built on a mid-length gas system rather than the rifle-length system used on the other 18-inch S2W barrel.

Mid-length gas at 18 inches is the pragmatic version of a heavy 5.56 build. You keep the length and the mass that make this profile shoot well, but the gas block sits closer to the receiver than a rifle-length system would place it, which means a shorter handguard covers it and mid-length gas tubes are far easier to source than rifle-length ones.

S2W is the company’s Strength to Weight profile, described as its proprietary Heavy Barrel. Daniel Defense lists the stripped barrel at 2.65 lbs, which is nearly a pound more than a 16″ Lightweight barrel. The mass buys thermal capacity for long strings of fire and the stiffness that keeps groups tight and point of impact stable as the barrel warms. It is a barrel for deliberate shooting rather than for carrying.

Key Facts

• Brand: Daniel Defense
• Model: 18″ 5.56mm, Mid-length, 1:7, S2W
• Manufacturer Part Number: 07-116-11192
• Caliber: 5.56mm NATO
• Barrel Length: 18″
• Twist Rate: 1:7
• Barrel Profile: S2W (Daniel Defense proprietary Heavy Barrel)
• Gas System: Mid-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 (stripped barrel): 2.65 lbs
• Barrel Configuration: With low profile gas block

Mid-length versus rifle-length on an 18-inch heavy barrel

The rifle-length version of this same S2W barrel gives the lowest port pressure and longest dwell available on the platform, and Daniel Defense lists it at 2.81 lbs stripped. The mid-length version here is lighter at 2.65 lbs stripped and places the gas block further back, which lets a shorter handguard cover it and keeps the front end less extended.

Weight figures and what we will not guess at

Daniel Defense lists 2.65 lbs for the 18″ S2W mid-length barrel, and there is no published assembled weight for this length and gas system with the low profile gas block fitted. Rather than borrow a figure from the rifle-length barrel, we will leave it open: call 817-393-4000 and we will weigh one from stock if you need the number for a build calculation.

Match this with a handguard from our rails and handguards, browse our upper receiver parts for the rest of the upper, or compare configurations in our Daniel Defense barrels.

Ordering from Western Sport in Roanoke, TX

We are a Daniel Defense master dealer in Roanoke, Texas with a licensed FFL and SOT held since 2007 and a gunsmith on site. If you would rather collect a finished, headspaced upper than a box of parts, call 817-393-4000 and we will build it.

Frequently Asked Questions

Q: What is the difference between this and the rifle-length 18″ S2W barrel?

A: The gas system. This one is mid-length, which puts the port closer to the chamber, gives a slightly firmer impulse, and uses more widely available mid-length gas tubes. The rifle-length version has the lowest port pressure and longest dwell for the softest cycle, and Daniel Defense lists it at 2.81 lbs stripped against 2.65 lbs here.

Q: What weight should I plan for?

A: Daniel Defense lists 2.65 lbs for the stripped 18″ S2W mid-length barrel. No assembled figure is published for this configuration with the low profile gas block fitted, so we will not quote one. Call 817-393-4000 and we will weigh one from stock if you need an exact number.

Q: Which gas tube does this barrel require?

A: A mid-length gas tube. This barrel uses a mid-length gas system, so neither a carbine nor a rifle-length tube will fit correctly. Getting the tube length wrong will stop the rifle cycling, so order the mid-length tube deliberately rather than relying on whatever came with a generic parts kit.

Q: Is the S2W profile too heavy for a general-purpose rifle?

A: For most general-purpose use, yes. At 2.65 lbs bare it is nearly a pound heavier than a 16″ Lightweight barrel, and with a long handguard and optic the finished rifle is nose-forward. Its strengths are thermal capacity and stiffness for long strings, which suit marksman and competition builds rather than carry guns.

Q: Can a free-float handguard cover the gas block?

A: Yes. The low profile gas block configuration exists for exactly that, allowing a continuous M-LOK or KeyMod tube over the block and an unbroken top rail. Mid-length gas places the block closer to the receiver than rifle-length would, so a shorter handguard will cover it than the rifle-length version needs.

Q: Is 18 inches legal without NFA registration?

A: Yes, as a rifle. Eighteen inches is well above the federal 16-inch minimum barrel length, so there is no registration, tax stamp or permanently attached muzzle device requirement. State and local law can differ from federal law, so confirm the rules in your own jurisdiction before building.

Additional information