BCM Milspec Carbine Stock Hardware Mounting Kit for AR-15
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits AR-15/M4 lower receivers with a standard threaded rear, including UK straight-pull AR-15 builds. Takes Mil-Spec dimension stocks from BCM, VLTOR, LMT, Magpul CTR-M, Stag Arms and Colt. No stock is included in this kit.
Not sure it fits your rifle? Ask us before you order
The BCM Milspec Carbine Stock Hardware Mounting Kit is a complete receiver extension assembly for AR-15 and M4 rifles — buffer tube, receiver end plate, castle nut, carbine action spring and carbine buffer — and it does not include a stock.
There is no stock in this box. This is the hardware that mounts a Mil-Spec stock you already own.
Bravo Company USA's name for this kit mentions a stock, and some retailers list the same part more plainly as a buffer tube assembly, which is what it actually is. You get the Mil-Spec 6-position receiver extension machined from 7075-T6 aluminium, the receiver end plate, the M4 castle nut, the carbine action spring and the carbine buffer assembly. Bolt those to a lower receiver and you have everything a Mil-Spec stock needs to slide onto — except the stock.
That makes it the right purchase when you already have a serviceable stock and want fresh, correctly specified hardware behind it, or when you are building a lower from parts and want the tube assembly from one manufacturer. If you want the stock as well, the Gunfighter Stock Kit Mod 0 in Black is this same hardware supplied with the Mod 0 stock fitted. Ordering this kit expecting a stock is the single most common mistake on this part, so it is worth a second look before you check out.
Fits AR-15/M4-pattern lower receivers with a standard threaded rear, including UK straight-pull AR-15 builds, where the buffer and action spring return the carrier after each hand-cycled stroke. Bravo Company USA lists the kit as compatible with Mil-Spec dimension stocks from BCM, VLTOR, LMT, Magpul CTR-M, Stag Arms and Colt. Because the receiver extension is Mil-Spec diameter, a commercial-diameter stock will not fit it. Remember that no stock is supplied: you must already have one, or buy one separately. Fitting needs a castle-nut wrench, and the castle nut should be torqued and staked or thread-locked.
| Platform | AR-15 / M4 |
|---|---|
| Fits | AR-15/M4 lower receivers with a standard threaded rear; Mil-Spec dimension stocks |
| Type | Stock mounting hardware — receiver extension, receiver end plate, castle nut, carbine action spring, carbine buffer. No stock included |
| Material | 7075-T6 aluminium receiver extension |
| Adjustment | 6-position receiver extension |
| Brand | Bravo Company USA |
| MPN | BCM-STOCK-HARDWARE-KIT |
The hardware, correctly specified, with no stock you did not ask for. Order the Milspec Carbine Stock Hardware Mounting Kit today — imported from the USA with all duties paid by us and dispatched tracked from the UK in 7–10 business days, with nothing to pay on delivery.
Explore more: AR-15 Parts & Accessories, Rifle & Shotgun Stocks or browse all Bravo Company USA.
| Platform | AR-15 / M4 |
|---|---|
| Fits | AR-15/M4 lower receivers with a standard threaded rear; Mil-Spec dimension stocks |
| Type | Stock mounting hardware — receiver extension, receiver end plate, castle nut, carbine action spring, carbine buffer. No stock included |
| Material | 7075-T6 aluminium receiver extension |
| Adjustment | 6-position receiver extension |
| Brand | Bravo Company USA |
| MPN | BCM-STOCK-HARDWARE-KIT |
| Category | Lower Parts |
| Barcode | 855877004404 |
£5 tracked UK delivery on every order via Royal Mail Tracked 24. Our products are ordered in from the manufacturer rather than held in UK stock, so please allow 7 to 10 business days (Monday to Friday, excluding bank holidays) from the date of your order for it to reach you. Tracking details are emailed on dispatch. UK delivery only.
You have 30 days from receiving your order to cancel it for any reason, then 14 days to send it back unused and in its original packaging. Faulty, damaged or incorrect items are replaced or refunded and we cover reasonable return postage. Refunds go back to your original payment method within 14 days of receiving the return.
No. Despite the name, there is no stock in this box. You get the receiver extension (buffer tube), receiver end plate, castle nut, carbine action spring and carbine buffer only. If you want the same hardware supplied with a stock, order the <a href="/products/bcm-gunfighter-stock-kit-mod-0-black">Gunfighter Stock Kit Mod 0 in Black</a> instead.
The receiver extension is Mil-Spec diameter, so it takes Mil-Spec dimension stocks. Bravo Company USA lists compatibility with stocks from BCM, VLTOR, LMT, Magpul CTR-M, Stag Arms and Colt. Commercial-diameter stocks are slightly larger and will not fit, so check what you have before ordering.
Yes. The receiver extension houses the buffer and action spring, which return the carrier after you cycle the rifle by hand. Any AR-15/M4 lower receiver with a standard threaded rear will take the assembly.
A castle nut wrench and a way to hold the lower receiver securely. The end plate goes on first, then the tube threads in, the buffer and spring drop in, and the castle nut is torqued and staked or thread-locked against the end plate. If you would rather not do that yourself, have a gunsmith fit it.
Parts are sent from the United Kingdom with £5 tracked UK delivery in 7–10 business days, and tracking is emailed to you when the parcel ships. If a part turns out to be the wrong fit, see our returns policy or <a href="/pages/contact">contact us</a> and we'll help sort it.
7 to 10 business days from the date of your order. Every order is sent Royal Mail Tracked for a flat £5 and you receive tracking details by email when it is dispatched.
Yes. We list only genuine parts and optics from the brands shown, ordered in from the manufacturer for your order.
Compatibility notes on this page come from the manufacturer. If you are unsure, email us with your make and model before ordering and we will check rather than guess.
Yes. Bundle & Save applies automatically in your basket: 5% off when you buy 2 items, 10% off at 3 items and 15% off at 4 or more. It works across the whole range, so you can mix and match, and there is no code to enter.
Yes — you have 30 days from delivery to cancel for any reason, as long as the item is unused and in its original packaging. See our returns policy for the details.
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