Primary Arms SLx Cantilever 34mm Scope Mount

The Primary Arms SLx Cantilever 34mm Scope Mount is a one-piece cantilever mount for 34mm-tube scopes, built to hold zero through hard use without the premium price tag. The cantilever design pushes the rings forward for correct scope placement and eye relief on an AR-pattern rifle, and it sets your optic at a 1.5" optical centerline. It's the same proven mount as the 30mm version, sized for the larger 34mm tubes found on many higher-end LPVOs and long-range scopes.

The clamping system is what makes it dependable. A three-bolt cross-bolt design spreads recoil evenly and generates over 6,500 lbs of clamping force, backed by dual machined recoil lugs and three cross-bolt lugs, so it resists heavy recoil and sustained fire without shifting zero. It's machined from 6061 aluminum with steel hardware and a hardcoat anodized finish, weighs 5.785 oz, has a true 0 MOA cant, and carries Primary Arms' lifetime warranty.

This is the 34mm version, for scopes with a 34mm main tube (confirm your scope's tube size, it's a different mount than the 30mm). To add an offset red dot for close-range work, pair it with the matching SLx 34mm Top Cap Reflex Mount. Browse the rest of our optics and mounts here.

34mm or 30mm?

Match the mount to your scope's tube diameter. This 34mm version fits 34mm-tube scopes; if your scope has a 30mm tube, you need the SLx Cantilever 30mm Mount instead. Tube size is listed in your scope's specs, don't guess, since the ring diameter has to match exactly.

Add an Offset Red Dot

The SLx 34mm Top Cap Reflex Mount bolts onto this mount and holds a mini reflex sight above your scope for a fast close-range aiming option. It fits the popular Holosun 507C footprint, so dots like the Holosun 507C or 407C mount right up.

Key Features

• One-piece cantilever. Correct scope placement and eye relief on AR-pattern rifles.
• 1.5" optical centerline. Standard co-witness-friendly height.
• 0 MOA cant. Neutral mounting for standard use.
• Three-bolt clamp. Over 6,500 lbs of clamping force, evenly distributed.
• Dual recoil lugs. Plus three cross-bolt lugs to resist recoil and hold zero.
• Tough and light. 6061 aluminum, steel hardware, hardcoat anodized, 5.785 oz.
• Lifetime warranty. Backed by Primary Arms.

Specs

• Type: One-piece cantilever scope mount
• Ring size: 34mm
• Optical centerline: 1.5"
• Cant: 0 MOA
• Clamping force: Over 6,500 lbs (three-bolt design)
• Recoil lugs: Dual machined recoil lugs + 3 cross-bolt lugs
• Material: 6061 aluminum, steel hardware
• Finish: Hardcoat anodized, black
• Rail: MIL-STD-1913 Picatinny
• Ring torque: 16–18 in-lbs
• Base torque: 30–35 in-lbs
• Weight: 5.785 oz
• Warranty: Primary Arms lifetime

FAQ

Will this fit my scope?
It fits scopes with a 34mm main tube. Confirm your scope's tube diameter in its specs. If it's 30mm, you need the SLx Cantilever 30mm mount instead, the ring size has to match exactly.

Why a cantilever mount?
On AR-pattern rifles, the receiver forces the scope too far back for proper eye relief. A cantilever mount pushes the rings forward so you can position the scope correctly, which is why they're the standard for LPVOs and variable scopes on ARs.

Will it hold zero?
Yes. The three-bolt clamp delivers over 6,500 lbs of clamping force, and dual recoil lugs plus three cross-bolt lugs keep it locked to the rail through heavy recoil without shifting zero.

Can I add a red dot?
Yes. The matching SLx 34mm Top Cap Reflex Mount bolts on top and holds a 507C-footprint mini reflex sight above the scope for fast close-range transitions.