Installation Instructions

Use these instructions for Armadyne direct mounts and ModMount components. Confirm that the mount matches the firearm receiver and optic footprint before beginning, and review any optic-specific hardware note supplied with the mount.

Before you begin

Unload the firearm completely. Remove the magazine, clear the chamber, and keep the firearm pointed in a safe direction throughout installation.

Use an inch-pound torque driver for final assembly. Do not substitute receiver hardware unless the replacement has been verified for the same thread, length, and head style.

Check optic screw length first

  1. Place the optic on the mount and loosely install screws with the correct thread. Use the optic manufacturer's screws when their thread and length are correct; included optic screws are supplied as a convenience.
  2. Confirm that the screws do not extend below the mount where they could contact the firearm receiver.
  3. With the optic attached, dry-fit the mount on the receiver and visually confirm that no optic screw can touch or scratch the receiver.
  4. Remove the optic if needed to reach the receiver screws, then install it again after the mount is secured.

Choose your platform

Open the section that matches your firearm receiver and mount design.

Ruger Mark IV

Standard and skeletonized mounts Standard three-hole receiver; front two holes

These mounts fit the standard three-hole receiver pattern and use the two threaded holes ahead of the ejection port. Remove the factory rail or other mount, position the Armadyne mount over the front two holes, and secure it with two #6-48 x 3/16 cap-head screws.

If the optic has a bottom O-ring, use a non-skeletonized mount so the O-ring rests on a continuous surface.

Midmount Standard three-hole receiver; spans the ejection port

The Midmount uses the threaded hole immediately ahead of the ejection port and the threaded hole behind it. Secure the mount with two #6-48 x 1/8 flat-head screws.

Standard ModMount Standard three-hole receiver; modular two-part system

Use the ModMount base made for the standard three-hole receiver. Position the base so its receiver holes align without force, then secure it with two #6-48 x 1/8 flat-head screws.

If a spacer is used, place it between the base and optic-side mount. Seat the mount's oval stud fully in the recessed oval interface and secure the assembly with two flat-head M4 screws. Spacers are optional and sold separately unless otherwise stated.

Riton-Equipped mounts Ruger Mark IV 22/45 Lite models 43946, 43947, and 43948

Remove the factory Riton red-dot mount, position the Armadyne mount in the same rear location, and secure it with two #6-48 x 1/8 cap-head screws.

Silencer Shop Exclusive mounts Four-hole receiver; matching front or rear hole pair

This receiver has two threaded holes ahead of the ejection port and two behind it. A compatible Armadyne mount can be installed on either matching hole pair. Secure it with two #6-48 x 1/8 cap-head screws.

Silencer Shop Exclusive ModMount Four-hole receiver; modular two-part system

Use the ModMount base made for the Silencer Shop Exclusive four-hole receiver. Position the base so its receiver holes align without force, then secure it with two #6-48 x 1/8 flat-head screws.

If a spacer is used, place it between the base and optic-side mount. Seat the mount's oval stud fully in the recessed oval interface and secure the assembly with two flat-head M4 screws. Spacers are optional and sold separately unless otherwise stated.

Ruger 10/22

Direct mounts Standard four-hole tapped receiver; front or rear position

Remove the factory rail or other mount. The Armadyne direct mount has three receiver-side holes so it can align with either the front pair or the rear pair of threaded receiver holes. Choose the mounting position, align the two matching holes without force, and secure the mount with two #6-48 x 3/16 cap-head screws.

ModMount base Standard four-hole tapped receiver; modular two-part system

Use the Ruger 10/22 ModMount base and orient it so its receiver holes align naturally with the compatible receiver holes. Do not force the alignment. Secure the base with two #6-48 x 3/16 cap-head screws.

If a spacer is used, place it between the base and optic-side mount. Seat the mount's oval stud fully in the recessed oval interface and secure the assembly with two flat-head M4 screws. Spacers are optional and sold separately unless otherwise stated.

The discontinued Ruger .44 Magnum Stalker uses the same receiver pattern and is also compatible with this mount line.

Beretta A300/1301

Direct mounts Tapped A300 or 1301 receiver; two M4 screws

These mounts fit Beretta A300 and 1301 shotguns with tapped receivers. Remove the factory rail or other mount, position the Armadyne mount over the threaded receiver holes, and secure it with two M4 x 0.7 x 6 mm screws.

Co-witness depends on the exact optic and mount combination. Use only a sight-picture statement confirmed for the specific optic being installed.

Stoeger M3000/M3500

Direct mounts Tapped receiver; screw size follows the serial number

These mounts fit Stoeger M3000 and M3500 shotguns with tapped receivers. Models before serial number 1368845 use two #6-48 x 1/8 flat-head receiver screws. Serial number 1368845 and later use two #8-40 x 3/16 flat-head receiver screws.

If both screw sets are included, use only the pair that matches the shotgun's serial-number range. Remove the factory rail or other mount, align the Armadyne mount with the receiver holes without force, and tighten the correct screws to the value in the torque table below.

ModMount base Tapped receiver; modular two-part system

Use the Stoeger M3000/M3500 ModMount base. Models before serial number 1368845 use two #6-48 x 1/8 flat-head receiver screws. Serial number 1368845 and later use two #8-40 x 3/16 flat-head receiver screws. If both screw sets are included, use only the pair that matches the shotgun's serial-number range.

If a spacer is used, place it between the base and optic-side mount. Seat the mount's oval stud fully in the recessed oval interface and secure the assembly with two flat-head M4 screws. Spacers are optional and sold separately unless otherwise stated.

11mm Dovetail

Complete ModMount 11mm-wide rail; 60-degree dovetail profile

Measure the rail before installation. A compatible rail is 11mm wide, approximately 0.43 inch across the top from point to point, with a 60-degree dovetail profile. A common 3/8-inch dovetail is approximately 0.50 inch across the top and requires the 3/8 Dovetail base.

Loosen the preinstalled #6-32 clamp screw enough to seat the base fully on the rail. Tighten the clamp screw to the #6-32 value in the torque table below.

If a spacer is used, place it between the base and optic-side mount. Seat the mount's oval stud fully in the recessed oval interface and secure the assembly with two flat-head M4 screws. Spacers are optional and sold separately unless otherwise stated.

Torque and thread locker

Thread locker is optional, and no special surface preparation is required. If liquid thread locker is used, reduce the applicable torque by 25 percent.

  • M4: 10 in-lb dry; 7.5 in-lb with liquid thread locker.
  • M3: 6 in-lb dry; 4.5 in-lb with liquid thread locker.
  • #6-32: 7 in-lb dry; 5.25 in-lb with liquid thread locker.
  • #6-48: 10 in-lb dry; 7.5 in-lb with liquid thread locker.
  • #8-40: 15 in-lb dry; 11.25 in-lb with liquid thread locker.

Final checks

  1. Confirm that the mount is fully seated and every screw is tightened to the applicable torque.
  2. Confirm again that no optic screw protrudes far enough to contact the receiver.
  3. Verify normal firearm operation before live fire.
  4. Recheck screw tension and optic zero after initial use.

For installation help, email support@armadynemfg.com with the firearm model, mount SKU, optic model, and a clear photograph of the installation.