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One Horse Rifles

16" .300 BLK AR-15 Rifle 15" M-LOK

This rifle ships free Rifles & Pistols Ship Free to your FFL

SKU OH-OG04UPC 850078799678

One Horse 16 inch .300 BLK AR-15 rifle with a 15 inch M-LOK handguard on a white background

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  • Limited Lifetime warranty
  • Ships to your dealer

How buying a rifle works

  1. Order online.Pick any options above, then check out.
  2. Choose your dealer.At checkout choose a dealer that is close to you for transfer.
  3. Pick it up.Your dealer checks your ID, runs the required background check and hands it over. You must be at least 18 to buy this rifle, or 21 where state or local law requires it.
What’s in the build

One Horse Rifle Specifications

Barrel
Caliber.300 BLK
Barrel ProfileSOCOM
Muzzle Thread5/8×24
Twist Rate1:7
Gas SystemPistol
Upper
Handguard Length15 in.
Charging HandleStandard
Lower
Buffer TubeMil-Spec
Furniture
GripA2
StockOne Horse M4 6 Position
In the box
Magazine30 Round Magazine
Test FiredEvery firearm is test fired before it ships
Customer Reviews

Reviews

Real feedback from customers who have experience with this product.

5.0
★★★★★
6 reviews
jeff G. Oct 29, 2026
★★★★★

Shot for the first time today. First shot was two inches low at 35 yards. Made an adjustment on my LPVO and put 19 rounds through a 1 1/2 inch hole. One Horse is an awesome company, ordered my rifle on a Sunday evening, got a conformation the next morning and received it on Thursday. This my second One Horse rifle.

Rick W. Aug 23, 2026
★★★★★

This is my first .300 blackout and so far im impressed. The rifle feels solid without being too heavy and the 15 inch handguard gives you plenty of room. Everything was tight out of the box and its ran good every time Ive taken it out.

Richard B. Jul 09, 2026
★★★★★

Really happy with this rifle. Nice MLOK rail, good build quality and no problems yet.

Steven Jun 30, 2026
★★★★★

I am a 100% permanent and totally disabled veteran. I recently got back into shooting, and my first rifle since leaving the service nearly 20 years ago is your OH2500333 .300 blackout. I cannot tell you enough how impressed I am with this rifle, especially given the top tier quality delivered at a fraction of the cost of more expensive and less reliable manufacturers. I feel like I cheated. For less than the cost of a diamondback or PSA, I got a something that rivals or surpasses a Saint Victor. I have full confidence in this rifle. I’m stoked I have one of the originals, and I’m looking forward to your 6mm ARC when I finally have the money for it. I had a feeling in my gut about this company, and seeing that it started with a fellow veteran sealed the deal for me. My instincts served me well, as there is not one single flaw with this rifle. Not. One. Well done.

Carl D. Jun 27, 2026
★★★★★

Solid .300 BLK for the price. Feels good, shoots smooth and has ran great so far.

John C. Jun 15, 2026
★★★★★

I bought this rifle because I wanted to get into .300 blackout without spending a crazy amount of money right away. For the price I wasnt sure what to expect, but it honestly surprised me when I picked it up. The upper and lower fit together nice, nothing rattles around and the finish looked good with no scratches or weird marks. The 15 inch MLOK handguard is comfortable and gives you plenty of space for whatever accessories you wanna add later. The rifle balances well and doesnt feel overly heavy when your standing and shooting. Stock and grip are pretty basic but they work fine, and thats easy stuff to change down the road if you want. Ive taken it out a few times now and its ran everything without giving me any trouble. Recoil feels smooth and it has been more accurate than I expected. I like that One Horse kept the rifle simple and affordable instead of adding a bunch of stuff I would probably replace anyway. Gives you a solid American made rifle that you can leave alone or build into whatever setup you want. Overall im really happy with it and would definately recommend it to somebody looking for a good entry into .300 BLK.

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About

16" .300 BLK AR-15 Rifle 15" M-LOK

The One Horse 16″ .300 BLK AR-15 Rifle (OH-OG04) is our 300 Blackout rifle: a 16″ SOCOM profile barrel with a 1:7 twist, pistol-length gas, a 5/8×24 muzzle thread with an A2 flash hider, and a 15″ M-LOK handguard.

.300 BLK and 5.56/.223 use the same BCG. Upgrading yours? See the 300 Blackout BCG.

Specs at a glance

  • .300 BLK caliber
  • 16″ SOCOM profile barrel with a 1:7 twist
  • Pistol-length gas system
  • 5/8×24 muzzle thread with an A2 flash hider
  • 15″ M-LOK handguard
  • A2 grip, One Horse M4 6 position stock and mil-spec buffer tube
  • One 30 round magazine in the box
  • 7.14 lbs.

Suppressor pairing

On .300 BLK, One Horse pairs only the Ryn .30 cal titanium suppressor. The Ryn comes with a Plan B mount included. Suppressors ship to your dealer, and you fill out a 4473 there before you take it home.

Upgrade the BCG

The rifle comes with the standard One Horse black nitride BCG. Gold TiN, Chameleon and Nickel BCGs are installed options above.

Made in America and backed by a Limited Lifetime warranty. Orders of $399 or more ship free.

16" .300 BLK AR-15 Rifle 15" M-LOK questions

How do I get my rifle?

At checkout choose a dealer that is close to you for transfer. We ship to that dealer and you pick it up there.

How old do I need to be?

You must be at least 18 to buy this rifle, or 21 where state or local law requires it.

Does it ship free?

Orders of $399 or more ship free.

Is there a warranty?

Yes. One Horse backs it with a Limited Lifetime warranty.

Ready when you are

Get your 16" .300 BLK AR-15 Rifle 15" M-LOK

Add to Cart
Ships freeLimited Lifetime warranty

Upgrade Your BCG

Extra Magazines!

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MSRP: Original price was: $679.99.Current price is: $579.99.

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