BCM 3 inch Picatinny Rail Section Aluminum for M-LOK
Mix and match across the range: 2 items save 5%, 3 save 10%, 4 or more save 15% on your whole basket.
Fits any M-LOK handguard or forend with room for a 3 inch section, on AR-15/M4 rifles including UK straight-pull AR-15 builds. M-LOK only — it will not attach to a KeyMod handguard. Accepts any 1913 Picatinny accessory once fitted.
Not sure it fits your rifle? Ask us before you order
The BCM 3 inch Picatinny Rail Section is an aluminium MIL-STD-1913 rail ladder for AR-15 and M4 rifles, bolting directly to any M-LOK handguard.
The adapter that lets an M-LOK handguard take Picatinny accessories — three inches of proper 1913 rail, where you want it and nowhere else.
M-LOK handguards are lighter and slimmer than quad rails precisely because they carry no rail they are not using. The cost of that is any accessory built for a Picatinny interface — a vertical grip, a light mount, a bipod adapter, an offset optic — has nothing to clamp to. This section solves it in one part: it fastens through the M-LOK slots and presents three inches of hard-anodised aircraft aluminium alloy machined to Mil-Standard 1913 Picatinny Arsenal specification.
The profile is deliberately snag-resistant, so it does not become the thing that catches on a sling or a bag every time the rifle moves. Mounting hardware and a hex key are supplied, so nothing else is needed to fit it.
Fits any M-LOK handguard or forend with the slot spacing to take a 3 inch section, on AR-15/M4 rifles including UK straight-pull AR-15 builds. It is an M-LOK part, so it will not attach to a KeyMod handguard or to an existing Picatinny rail. Once fitted it accepts any accessory built for a 1913 Picatinny interface. Position it before you tighten down — a section too far forward puts a light or grip where the support hand is not — then torque the fasteners with the supplied hex key and re-check them after the first session.
| Platform | AR-15 / M4 |
|---|---|
| Fits | M-LOK handguards and forends |
| Type | Picatinny rail section, MIL-STD-1913 |
| Material | Aircraft aluminium alloy |
| Finish | Hard anodised |
| Length | 3 in (76 mm) |
| Mount interface | M-LOK, mounting hardware and hex key included |
| Brand | Bravo Company USA |
| MPN | BCM-MCMR-1913-A3 |
Add rail only where the rifle needs it. Order the BCM 3 inch Picatinny Rail Section 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 | M-LOK handguards and forends |
| Type | Picatinny rail section, MIL-STD-1913 |
| Material | Aircraft aluminium alloy |
| Finish | Hard anodised |
| Length | 3 in (76 mm) |
| Mount interface | M-LOK, mounting hardware and hex key included |
| Brand | Bravo Company USA |
| MPN | BCM-MCMR-1913-A3 |
| Category | Rail Section |
| Barcode | 812526021588 |
£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. This is the M-LOK version and its fasteners engage M-LOK slots. KeyMod handguards need a KeyMod rail section instead. Check which system your handguard uses before ordering — M-LOK slots are plain rectangles, KeyMod slots have a round keyhole at one end.
Anything built for a 1913 Picatinny interface: vertical and angled foregrips, light mounts, bipod adapters, offset optic mounts, sling mounts and so on. That is the point of the part — it converts a section of M-LOK into the interface most accessories are still made for.
Yes. The mounting hardware and a hex key are supplied, so no separate purchase is needed. Torque the fasteners evenly and re-check them after the first range session, as with any rail-mounted hardware.
Yes. It is a handguard accessory and has nothing to do with how the rifle is cycled, so it fits straight-pull AR-15 builds exactly as it fits any other M-LOK handguard.
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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