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.
Why shooters choose the A/T Optic Riser
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0.525" (13.3 mm) rise on every version — a consistent, repeatable sightline whichever footprint you choose
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Angled Torque clamp — approximately twice the clamping force at the same torque as a horizontal interface
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Multiple integral recoil lugs — the riser engages the rail and holds zero rather than creeping
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Five footprints — from a 5-slot receiver-top riser to an 18-slot cantilever platform
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Usable stalk — Mil-Std 1913 attachments mount anywhere along the riser, not just on top
What the A/T Optic Riser fits
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.
Specifications
| 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 — in stock at Xtreme Tactical Gun Parts with free tracked UK delivery in 7–10 days.
Explore more: AR-15 Parts & Accessories, Iron Sights & Backup Sights or browse all Bravo Company USA.
