Optic Mount for Aimpoint COA to SIG P320 Sig-LOC Slide Cut

This optic mount is a direct-fit steel adapter designed to securely attach the Aimpoint COA to any SIG Sauer P320 slide machined with the factory Sig-LOC optic cut. The primary problem it solves: the COA uses the Aimpoint A-Cut footprint, which is not native to the Sig-LOC interface. Without this mount, the optic cannot be properly torqued or zeroed on those slides. The mount and clamp are machined from billet steel with a Black PVD finish, providing a rigid, corrosion-resistant platform that maintains zero under recoil and holster wear.

Compatibility

• SIG Sauer P320 Legion (all variants with Sig-LOC cut)
• SIG Sauer M17 / M18 (military and civilian models)
• Other P320 models featuring the factory Sig-LOC optic cut
• Compatible with factory Loaded Chamber Indicator on M17/M18 slides
• Requires Aimpoint COA optic (not included)

Key Features

• Material: Billet steel, Black PVD finish
• Geometry: Aimpoint A-Cut
• Mounting: Clamp-style, integrated into the optic cut channel
• Fasteners: All screws include pre-applied thread locking patch
• Torque spec: 15 in-lb for all Apex screws
• Origin: 100% manufactured in the USA
• Optional add-on (coming soon): Apex COA BUIS Set – replaces the clamp with an integrated rear sight, plus a matched-height front sight

Install Difficulty: 2 out of 5

Requires a torque driver capable of 15 in-lb (inch-pounds). No slide modification, filing, or fitting required. Remove the optic cover plate (if present), place the mount in the cut, position the COA, install the clamp, and torque screws to spec. Typical install time: 10–15 minutes.

FAQ

Will this fit a P320 that does not have the Sig-LOC cut?

No. This mount is designed exclusively for slides with the factory Sig-LOC optic cut. It will not fit standard RMR, Deltapoint Pro, or other footprint cuts.

Do I need to remove the factory Loaded Chamber Indicator on an M17/M18?

No. The mount is profiled to clear the LCI. No modification or removal of the indicator is required.

Can I use suppressor-height sights with the COA and this mount?

The optional Apex COA BUIS set (coming soon) includes a replacement clamp with an integrated rear sight and a matched front sight. Until that add-on is available, there is no direct co-witness option for this mount. Standard P320 sights will not co-witness.

Shipping: Ships within 1 business day. Warranty: This component is covered by the manufacturer’s lifetime warranty against defects in materials and workmanship. No registration required.