AR-15 Parts · Stocks
One Horse · Buyer’s guide
The One Horse AR-15 buttstock is a polymer, 6-position adjustable M4 stock made for a mil-spec carbine buffer tube. Here’s what fits, what else you need and what it costs.
The basics
The buttstock is the part you shoulder. On an AR-15 it slides onto the buffer tube at the back of the lower receiver. An adjustable M4-style stock locks into a set of positions, so you can set the length of pull for you, your gear and how you shoot.
The One Horse M4 buttstock has 6 positions and a polymer body. It is the same One Horse M4 6 position stock that comes on One Horse rifles and on the complete lower.
Mil-spec and commercial buffer tubes have different outside diameters. The OH-BS01 is a mil-spec diameter stock, so put it on a mil-spec tube.
Buttstock and buffer system
The stock, buffer tube and buffer work as one system. Prices are live from the store.
| Part | What it is | Price |
|---|---|---|
| Mil-Spec M4 Buttstock | Polymer, 6-position adjustable M4 stock | $29.99 |
| Carbine Buffer Tube Kit | Buffer tube, carbine buffer, carbine spring, castle nut and end plate | $45.99 |
| H1 Buffer | 3.8 oz. carbine buffer | $45.99 |
| H2 Buffer | 4.7 oz. carbine buffer | $72.99 |
| H3 Buffer | 5.6 oz. carbine buffer | $105.99 |
| Complete Lower Receiver | Lower with the M4 6 position stock, mil-spec buffer tube and A2 grip installed | $198.99 |
Our take
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SKU: OH-BT01
Free shipping on orders of $399 or more. The complete lower ships to your FFL dealer. Sold out? Click Notify Me When Available on the product page.
Building one?
Planning the rest of the build? See the AR-15 parts list, AR-15 lowers and the H1, H2 and H3 buffer chart.
Questions
The AR-15 Mil-Spec M4 Buttstock (OH-BS01): a polymer, 6-position adjustable M4-style stock. It is the same One Horse M4 6 position stock that comes on One Horse rifles and on the complete lower.
It is a mil-spec diameter stock, made for a mil-spec carbine buffer tube. Mil-spec and commercial buffer tubes have different outside diameters, so check which tube you have before you order.
Six. The M4 stock slides on the buffer tube and locks in one of six positions, so you can set your length of pull.
If your lower doesn’t have a buffer tube yet, yes. The AR-15 Carbine Buffer Tube Kit (OH-BT01) is a 6-position mil-spec carbine kit: buffer tube, carbine buffer, carbine spring, castle nut and end plate. Want a heavier buffer? See the H1, H2 and H3 buffer chart.
Yes. The AR15 Complete Lower Receiver comes with the One Horse M4 6 position stock, a mil-spec buffer tube and an A2 grip installed.
Yes. One Horse lists it as made in the U.S.A.
No. A buttstock is a part, so it ships to you. Check your state and local law before you order.
Orders of $399 or more ship free.
Yes. One Horse parts are backed by a Limited Lifetime warranty.
American Made · Family Owned · Veteran Owned
Stock, buffer tube and buffer, made in America.
Federal, state and local laws vary and change, and it is the buyer’s responsibility to follow them. Questions? Call 812-200-0305 or email customerservice@theonehorse.com.
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Free shipping on orders $399 or more
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