Kak Industry167527283
K-Spec 5.56 Nato 14.5'' Bbl 1-7 Twist Complete Upper Black$587.43
Availability: In Stock
Current Stock: Out of stock
The KAK Industry K-Spec 5.56 NATO complete upper with 13.9" barrel and 1-7 twist is a ready-to-run rifle upper built for shooters who want accuracy, reliability, and suppressor compatibility out of the box. This is a factory-assembled upper receiver—just bolt it to your lower and you're shooting. It pairs a chrome-lined 4150 CrMoV barrel with KAK's K-SPEC Enhanced BCG, a down-vent design that redirects gas downward instead of into your face, a significant advantage when running a suppressor with a traditional baffle can.
The 13.9" barrel length sits in that sweet spot for versatility: short enough for CQB and vehicle work, long enough to wring decent velocity from 5.56 without a permanent muzzle device. The 1-7 twist rate stabilizes everything from lightweight varmint rounds to heavy 77-grain match ammunition, so you're not locked into one load profile. You get a Brownells-exclusive PentaComp muzzle device (1/2x28 threaded) and a 13" M-LOK handguard with a heavy-duty barrel nut for a rock-solid shooting platform. The forged 7075 T6 upper receiver and large billet latch charging handle complete a package designed for years of service. Each upper is test-fired before it ships to confirm reliable function.
Built in the USA and engineered around mid-length gas system tuning, this upper works well for suppressed and unsuppressed shooting alike. If you're building a short-stroke AR or upgrading an existing lower, this complete upper eliminates guesswork and assembly headaches.
| Caliber | 5.56 NATO |
| Barrel Length | 13.9" |
| Barrel Twist Rate | 1:7" |
| Barrel Material | 4150 CrMoV, chrome-lined |
| Gas System | Mid-length |
| Muzzle Thread | 1/2x28 |
| Muzzle Device | Brownells PentaComp |
| Upper Receiver | Forged 7075 T6 |
| BCG | K-SPEC Enhanced, chrome-lined phosphate, down-vent design |
| Handguard | 13" M-LOK with heavy-duty barrel nut |
| Charging Handle | Large billet latch |
| Finish | Black |
Yes. This is a complete upper receiver assembly that accepts any standard AR-15 lower receiver. No additional work or parts are required—the upper is fully assembled and test-fired.
Yes. The K-SPEC Enhanced BCG features a down-vent design that redirects exhaust gas downward instead of toward the shooter's face, which is a significant advantage when running a suppressor with a traditional baffle can. The mid-length gas system also contributes to smooth suppressed operation.
The 1-7 twist rate is versatile and will stabilize a wide range of 5.56 NATO ammunition, from lightweight varmint rounds to heavy 77-grain match ammunition.
This is a complete upper receiver assembly ready to attach to a lower receiver. It includes the barrel, bolt carrier group, muzzle device, handguard, charging handle, and all necessary hardware. No additional parts are required to make it functional.
SKU: 167527286 • Weight: 5oz
Availability: In Stock
Current Stock: Out of stock
The KAK Industry K-Spec 5.56 NATO complete upper with 13.9" barrel and 1-7 twist is a ready-to-run rifle upper built for shooters who want accuracy, reliability, and suppressor compatibility out of the box. This is a factory-assembled upper receiver—just bolt it to your lower and you're shooting. It pairs a chrome-lined 4150 CrMoV barrel with KAK's K-SPEC Enhanced BCG, a down-vent design that redirects gas downward instead of into your face, a significant advantage when running a suppressor with a traditional baffle can.
The 13.9" barrel length sits in that sweet spot for versatility: short enough for CQB and vehicle work, long enough to wring decent velocity from 5.56 without a permanent muzzle device. The 1-7 twist rate stabilizes everything from lightweight varmint rounds to heavy 77-grain match ammunition, so you're not locked into one load profile. You get a Brownells-exclusive PentaComp muzzle device (1/2x28 threaded) and a 13" M-LOK handguard with a heavy-duty barrel nut for a rock-solid shooting platform. The forged 7075 T6 upper receiver and large billet latch charging handle complete a package designed for years of service. Each upper is test-fired before it ships to confirm reliable function.
Built in the USA and engineered around mid-length gas system tuning, this upper works well for suppressed and unsuppressed shooting alike. If you're building a short-stroke AR or upgrading an existing lower, this complete upper eliminates guesswork and assembly headaches.
| Caliber | 5.56 NATO |
| Barrel Length | 13.9" |
| Barrel Twist Rate | 1:7" |
| Barrel Material | 4150 CrMoV, chrome-lined |
| Gas System | Mid-length |
| Muzzle Thread | 1/2x28 |
| Muzzle Device | Brownells PentaComp |
| Upper Receiver | Forged 7075 T6 |
| BCG | K-SPEC Enhanced, chrome-lined phosphate, down-vent design |
| Handguard | 13" M-LOK with heavy-duty barrel nut |
| Charging Handle | Large billet latch |
| Finish | Black |
Yes. This is a complete upper receiver assembly that accepts any standard AR-15 lower receiver. No additional work or parts are required—the upper is fully assembled and test-fired.
Yes. The K-SPEC Enhanced BCG features a down-vent design that redirects exhaust gas downward instead of toward the shooter's face, which is a significant advantage when running a suppressor with a traditional baffle can. The mid-length gas system also contributes to smooth suppressed operation.
The 1-7 twist rate is versatile and will stabilize a wide range of 5.56 NATO ammunition, from lightweight varmint rounds to heavy 77-grain match ammunition.
This is a complete upper receiver assembly ready to attach to a lower receiver. It includes the barrel, bolt carrier group, muzzle device, handguard, charging handle, and all necessary hardware. No additional parts are required to make it functional.
SKU: 167527286 • Weight: 5oz