The One Horse 18" 6mm ARC AR-15: a complete HBAR rifle and a complete upper, made in America.
SKU OH-OG03UPC 850078799685
The same 18" HBAR barrel, twist and thread in 416R stainless.
Both fit the 5/8×24 muzzle thread.
Ryn .30 Cal SuppressorPlan B Included · pairs with the 6mm ARC$549.99 MSRP Ryn .30 Cal SuppressorPlan B Included · pairs with the 6mm ARCAvailable SoonNotify Me When Available| Spec | 18" 6mm ARC Rifle | 18" 6mm ARC Upper |
|---|---|---|
| SKU | OH-OG03 | OH-CU09 |
| Caliber | 6mm ARC | 6mm ARC |
| Barrel profile | HBAR | HBAR |
| Barrel material | — | 416R stainless |
| Twist rate | 1:7.5 | 1:7.5 |
| Muzzle thread | 5/8×24 | 5/8×24 |
| Gas system | Rifle-length | Rifle-length |
| Handguard | 15 in. | 15 in. |
| Grip / stock | A2 / One Horse M4 6 position | Not included |
| Buffer tube | Mil-Spec | Not included |
| Magazine | 6mm ARC compatible | Not included |
| Warranty | Limited Lifetime | Limited Lifetime |
Specs from the live product pages and One Horse.
Buy a 6mm ARC and the hat is free. The Blaze Orange Richardson 112 Limited Edition hat comes free with the complete 6mm ARC rifle.
Pick the 18" 6mm ARC HBAR Rifle (OH-OG03). A2 grip, One Horse M4 6 position stock, mil-spec buffer tube and a 6mm ARC compatible magazine. Ships to your dealer.
Pick the 18" 6mm ARC Complete Upper (OH-CU09). Same 18" 416R stainless HBAR barrel, 1:7.5 twist and rifle-length gas. It drops onto any mil-spec AR-15 lower and ships to you.
The Ryn .30 cal pairs with the 6mm ARC on the 5/8×24 thread. Plan B mount included; you fill out a 4473 at your dealer.
6mm ARC uses its own magazines and bolt. Don't assume a standard 5.56 magazine will work.
The 6mm ARC rifle from One Horse is an 18" HBAR AR-15 with a 1:7.5 twist, a 5/8×24 muzzle thread, a 15 in. M-LOK handguard, an A2 grip and a One Horse M4 6 position stock.
Already have a lower? The 6mm ARC upper uses the same 18" HBAR barrel profile, twist and thread in 416R stainless. Every One Horse rifle and component is made in America with U.S.-sourced materials and U.S. manufacturing.
The 6mm ARC (Advanced Rifle Cartridge) was developed by Hornady and introduced in 2020 for the AR-15 platform. It shoots long, high ballistic coefficient bullets. It is a good choice for hunting deer-size game and for precision shooting from an AR-15 size rifle. Check your state's hunting rules before you hunt with any cartridge.
Pick the complete 6mm ARC rifle for the full rifle. It ships to your dealer for pickup. Pick the 6mm ARC AR-15 upper if you own a mil-spec AR-15 lower. Both use an 18" HBAR barrel, a rifle-length gas system and a 15 in. M-LOK handguard.
The rifle lists a 6mm ARC compatible magazine in the box. 6mm ARC uses its own magazines, so do not assume a standard 5.56 magazine will work.
Both barrels have a 5/8×24 thread. The 5/8x24 Pike 3 Prong is a 3 prong flash hider and Plan B mount for 5/8×24 barrels. The Ryn .30 Cal pairs with the 6mm ARC and is offered as an add-on on the rifle page. Plan B mount included with the Ryn. The 5/8×24 Pike 3 Prong is available as an extra mount. See the Plan B mount guide.
Two: the 18" 6MM ARC AR-15 HBAR Rifle-Length 15" M-LOK complete rifle and the 18" 6mm ARC AR-15 Complete Upper.
Both list a 1:7.5 twist and a 5/8×24 muzzle thread with an HBAR barrel profile.
The complete upper drops onto any mil-spec AR-15 lower.
Buy the complete rifle if you want the whole gun, with the A2 grip, One Horse M4 6 position stock and a 6mm ARC compatible magazine. Buy the complete upper if you already own a mil-spec AR-15 lower. Both use the same 18" HBAR barrel, 1:7.5 twist and 5/8×24 thread.
No. A complete upper is not the serialized part, so it ships straight to you. Check your state and local law before you order. The complete rifle ships to your FFL dealer.
The Ryn .30 cal. It fits the 5/8×24 thread with the Plan B mount included. The Ryn ships to your dealer, where you fill out a 4473 and take it home once approved.
Yes, with the complete 6mm ARC rifle. Buy a 6mm ARC and the Blaze Orange hat is free. The offer is shown on the rifle product page.
Order online and choose a dealer close to you at checkout. We ship to that dealer. Your dealer checks your ID and runs the required background check. You must be at least 18 to buy this rifle, or 21 where state or local law requires it.
Yes. One Horse backs the rifle and the upper with a Limited Lifetime warranty.
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