BCM MCMR M-LOK Handguard for AR-15
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Fits AR-15/M4 upper receivers, including UK straight-pull AR-15 builds. Clears barrels up to 1.0" (25.4 mm) diameter. Supplied with a steel barrel nut, which replaces the existing barrel nut. Handguard must clear the gas block — measure from the receiver face to the gas block before choosing a length.
Not sure it fits your rifle? Ask us before you order
The BCM MCMR is a free-float M-LOK handguard for AR-15 and M4 rifles, clamping to a mil-spec barrel nut and carrying a continuous 1913 Picatinny top rail.
Free-float rigidity, M-LOK where you want it, and nothing you do not need — the MCMR is the handguard BCM built around the shot, not the catalogue.
MCMR stands for M-LOK Compatible Modular Rail, and the name is the whole design brief. The tube is machined from 6061-T6 aluminium and hard-coat anodised to Mil-A-8625F Type III Class 2, then locked to a steel barrel nut by BCM's patented indexing and lock-up system (US Patent 8904691) so the top rail stays in line with the receiver rail under heat and under load.
Because it free-floats, nothing you bolt to the handguard touches the barrel. A bipod, a sling under tension, a hand pulled hard into a barricade — none of it deflects the barrel or moves the group. That is the single biggest accuracy return available on a UK straight-pull AR-15, where every shot is a deliberate, aimed shot and the rifle spends its life on bags, bipods and barricades rather than being run at speed.
The profile is slim — M-LOK slots sit at 3, 6 and 9 o'clock with an uninterrupted Picatinny rail along the top, so backup sights, night vision and lights index off one continuous plane. An M-LOK sling mount is supplied with the handguard.
Fits AR-15/M4 upper receivers, including UK straight-pull AR-15 builds, and clears barrels up to 1.0" (25.4 mm) in diameter. The supplied steel barrel nut replaces your existing nut, so the handguard is a barrel-off or at least a barrel-nut-off job — not a slip-on swap. Shorter tubes suit pistol- and carbine-length gas systems with a low-profile gas block; longer tubes cover mid-length systems and can be run over a fixed front sight base where the length allows. Measure from the receiver face to the gas block before choosing a length, because the handguard must clear the block, not sit on it.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Mil-spec upper receivers; barrels up to 1.0" (25.4 mm) diameter |
| Type | Free-float M-LOK handguard with full-length 1913 top rail |
| Material | 6061-T6 aluminium |
| Finish | Hard-coat anodised, Mil-A-8625F Type III Class 2 |
| Weight | 7" 4.8 oz (135 g) · 8" 5.3 oz (150 g) · 9" 5.9 oz (165 g) · 10" 6.6 oz (185 g) · 13" 8.2 oz (230 g) · 15" 9.2 oz (260 g); mounting hardware 2.3 oz (65 g) |
| Length | 7.39" (188 mm) · 8.14" (207 mm) · 9.4" (239 mm) · 10.5" (267 mm) · 13.4" (340 mm) · 15.0" (381 mm) |
| Mount interface | M-LOK slots at 3, 6 and 9 o'clock; continuous 1913 Picatinny top rail |
| Brand | Bravo Company USA |
| MPN | BCM-MCMR-7-556-BLK · BCM-MCMR-8-556-BLK · BCM-MCMR-9-556-BLK · BCM-MCMR-10-556-BLK · BCM-MCMR-13-556-BLK · BCM-MCMR-15-556-BLK |
Give the barrel room to shoot. Order the MCMR 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: M-LOK Accessories, AR-15 Parts & Accessories or browse all Bravo Company USA.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Mil-spec upper receivers; barrels up to 1.0" (25.4 mm) diameter |
| Type | Free-float M-LOK handguard with full-length 1913 top rail |
| Material | 6061-T6 aluminium |
| Finish | Hard-coat anodised, Mil-A-8625F Type III Class 2 |
| Weight | 7" 4.8 oz (135 g) · 8" 5.3 oz (150 g) · 9" 5.9 oz (165 g) · 10" 6.6 oz (185 g) · 13" 8.2 oz (230 g) · 15" 9.2 oz (260 g); mounting hardware 2.3 oz (65 g) |
| Length | 7.39" (188 mm) · 8.14" (207 mm) · 9.4" (239 mm) · 10.5" (267 mm) · 13.4" (340 mm) · 15.0" (381 mm) |
| Mount interface | M-LOK slots at 3, 6 and 9 o'clock; continuous 1913 Picatinny top rail |
| Brand | Bravo Company USA |
| MPN | BCM-MCMR-7-556-BLK · BCM-MCMR-8-556-BLK · BCM-MCMR-9-556-BLK · BCM-MCMR-10-556-BLK · BCM-MCMR-13-556-BLK · BCM-MCMR-15-556-BLK |
| Category | Handguard |
| Barcode | 812526021656 |
£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.
Measure from the upper receiver face to the front of your gas block and pick the longest tube that still clears it. On a carbine-gas 16" barrel with a low-profile gas block, 9" to 13" is the usual answer; 15" suits mid-length gas on a 16" or longer barrel. The 7" and 8" tubes are for short barrels or where you want a lot of exposed barrel. If the handguard would sit over the gas block, go one size shorter.
Yes. The handguard clamps to a steel barrel nut at the receiver and touches nothing else, so the barrel hangs free inside it. Anything you load the handguard with — a bipod, a sling pulled tight, a hand braced on a barricade — puts no bending force into the barrel. On a straight-pull AR-15 shot deliberately from support, that is where the accuracy gain comes from.
The handguard ships with its steel barrel nut and mounting hardware, plus a BCM M-LOK sling mount. Fitting means removing the existing handguard and barrel nut and torquing the new nut, so you need an armourer's wrench, a vice block and a torque wrench. If you are not set up for that, have a gunsmith fit it.
Any M-LOK-standard accessory bolts straight to the 3, 6 and 9 o'clock slots — rail sections, light mounts, hand stops, QD sling mounts. Picatinny accessories mount on the top rail, or on an M-LOK Picatinny rail section fitted to the side or bottom. KeyMod accessories do not fit; the MCMR is M-LOK only.
Handguards are sent from the United Kingdom with £5 tracked UK delivery in 7–10 business days, and you will get tracking by email when it 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 will 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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