BCM A/T Optic Riser 0.525" for AR-15
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Fits any Mil-Std 1913 Picatinny receiver rail on an AR-15/M4, including UK straight-pull AR-15 builds, and takes any optic or mount with a 1913 clamp. All five versions rise by the same 0.525" (13.3 mm) — the trailing number is recoil-slot count, not height, and X5 denotes a 5-slot cantilever section projecting forward of the main body.
Not sure it fits your rifle? Ask us before you order
The BCM A/T Optic Riser is a 0.525" Picatinny riser for AR-15 and M4 rifles, raising any 1913-mounted optic onto a longer, higher rail platform via BCM's angled-torque clamp.
One rise, five footprints — the A/T riser lifts the sightline 0.525" and gives you the rail length to put the optic, the magnifier and the night vision exactly where they belong.
Every one of the five versions rises by the same 0.525" (13.3 mm). What changes between them is footprint: how many recoil slots the riser carries and how far it extends over or forward of the receiver. That rise puts a typical lower-third optic at roughly 2.16" (55 mm) of optical centreline and an absolute-cowitness optic at roughly 1.93" (49 mm) — a head-up posture that is easier to hold, easier to hold consistently, and easier to work under night vision or with eye protection and a helmet.
The A/T in the name is Angled Torque: a patented clamp that applies triangulating force rather than pulling straight sideways, giving approximately twice the clamping force at the same torque as a legacy horizontal interface. Multiple integral recoil lugs engage the receiver rail so the riser cannot creep. The body is aircraft aluminium alloy, hard-coat anodised to Mil-A-8625F, with a nitride-coated steel clamp.
On a UK straight-pull AR-15 the case is straightforward. The rifle is worked by hand over the top of the receiver and shot deliberately from support, so a higher, longer optic platform means a more natural head position and room to lay out a red dot, a magnifier and a backup sight on one continuous plane instead of fighting for space on the receiver rail. The low-profile A/T interface keeps the whole assembly snag-free and leaves the riser stalk usable for bolt-on or QD accessories along its length.
Fits any Mil-Std 1913 Picatinny receiver rail on an AR-15/M4, including UK straight-pull AR-15 builds, and accepts any optic or mount with a 1913 clamp. Choose by footprint, not by height — all five rise by the same 0.525". The 5-slot is a compact riser for a red dot alone; the 11-slot and 13-slot give room for a magnifier, night vision or thermal behind the optic, with the 13-slot covering the full length of the upper receiver. The 10X5 and 13X5 add a 5-slot cantilever section projecting forward of the main body for layering a magnifier ahead of the receiver — the X5 is a rail section, not a different height. Check the riser length against your handguard's top rail so the cantilever has somewhere to sit.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Any Mil-Std 1913 Picatinny receiver rail; optics and mounts with a 1913 clamp |
| Type | Optic riser, 0.525" (13.3 mm) rise, A/T angled-torque clamp |
| Material | Aircraft aluminium alloy; steel alloy clamp, nitride coated |
| Finish | Hard-coat anodised, Mil-A-8625F |
| Length | 5-slot approx. 2⅛" (54 mm) · 11-slot approx. 4.5" (114 mm) · 13-slot approx. 5¾" (146 mm) · 10-slot + 5-slot cantilever approx. 6⅛" (156 mm) · 13-slot + 5-slot cantilever approx. 7¼" (184 mm) |
| Mount interface | A/T angled-torque clamp to Mil-Std 1913 Picatinny, with multiple integral recoil lugs |
| Brand | Bravo Company USA |
| MPN | BCM-OR-AT-525-5 · BCM-OR-AT-525-11 · BCM-OR-AT-525-13 · BCM-OR-AT-525-10X5 · BCM-OR-AT-525-13X5 |
Get your head up and your optics in line. Order the A/T Optic Riser 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, Scope Mounts & Optic Risers or browse all Bravo Company USA.
| Platform | AR-15 / M4 |
|---|---|
| Fits | Any Mil-Std 1913 Picatinny receiver rail; optics and mounts with a 1913 clamp |
| Type | Optic riser, 0.525" (13.3 mm) rise, A/T angled-torque clamp |
| Material | Aircraft aluminium alloy; steel alloy clamp, nitride coated |
| Finish | Hard-coat anodised, Mil-A-8625F |
| Length | 5-slot approx. 2⅛" (54 mm) · 11-slot approx. 4.5" (114 mm) · 13-slot approx. 5¾" (146 mm) · 10-slot + 5-slot cantilever approx. 6⅛" (156 mm) · 13-slot + 5-slot cantilever approx. 7¼" (184 mm) |
| Mount interface | A/T angled-torque clamp to Mil-Std 1913 Picatinny, with multiple integral recoil lugs |
| Brand | Bravo Company USA |
| MPN | BCM-OR-AT-525-5 · BCM-OR-AT-525-11 · BCM-OR-AT-525-13 · BCM-OR-AT-525-10X5 · BCM-OR-AT-525-13X5 |
| Category | Optic Mount |
| Barcode | 812526023872 |
£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. All five rise by exactly 0.525" (13.3 mm). The number in the part code is the count of recoil slots, which sets how long the riser is and how much rail you get — not how high it sits. An X5 code means a 5-slot cantilever section projecting forward of the main body, again at the same 0.525" rise.
Measured at the optical centreline, an optic that normally sits at lower-third cowitness ends up at approximately 2.16" (55 mm), and an absolute-cowitness optic ends up at approximately 1.93" (49 mm). The exact figure depends on the mount you clamp to the riser, so work from your own mount's published height plus 0.525".
For a red dot on its own, the 5-slot is enough. For a red dot with a magnifier behind it, or night vision or thermal in line, take the 11-slot or 13-slot — the 13-slot covers the whole upper receiver. The 10X5 and 13X5 carry a 5-slot cantilever forward of the receiver, which is what you want when the magnifier or a second device needs to sit ahead of the optic.
It applies torque at an angle so the clamp force triangulates onto the rail instead of pulling sideways, which BCM states gives approximately twice the clamping force at the same torque as a conventional horizontal interface. Combined with multiple integral recoil lugs, that is what keeps the riser — and therefore your zero — where you put it.
Risers 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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