How to select your JMac Modular Mounting System.

Ready to purchase our MMS - Modular Mounting System and aren't quite sure what you need!?

Product Pages:

10.64" Handguard with Sling Loop Cut

10.64" Handguard without Sling Loop Cut

AKM Railed Gas Tube

Let's Dive in!

The Base System consists of an Upper Mount, Lower Mount and Lower Handguard.

The length of this handguard is dependent upon the firearm host as well as intended use.

The Base System includes a 1913 railed gas tube, that extends over the gas block, and optic mounting solutions that sit over the dust cover.

In an attempt to simplify selecting the proper length handguard, we developed a naming convention to describe the length visually, to help the end-user understand fit and function. Without measuring, one may find the proper length using the terms and chart below.

• Retainer Length – Extends to the factory lower handguard retainer.
• Gas Block Length – Extends to the muzzle side of the gas block and completely covers it. (Only applicable on firearms with seperate gas block and front sight)
• Optimal Length – Extends immediately behind muzzle threads. This is the longest possible handguard without covering the muzzle threads. (Does not limit muzzle device options)
• Muzzle Length – Extends over the muzzle threads, but not past the end of the muzzle. (Limits muzzle device options)
• Extended Length – Extends beyond the end of the muzzle, requires specific muzzle device types.

In most instances, a Kalashnikov that has a separate gas block and front sight, one would want to choose "Gas Block" length. While in combination, Front Sight Gas block application, one would choose "Optimal" length. 

Muzzle and/or extended length will give a more modern appearance but will require muzzled devices to fit inside the handguard (maximum 1.3")

Handguard length would be chosen for a more classic look with the ability to mount accessories

Prefer to shop by using actual measurements?

Let's keep it simple! By using a tape measure, start from your receiver and extend towards the muzzle. For example, 10.64” is exactly 10.64" from the receiver to the end of the handguard . See Examples Below:

Installation Instructions

Before MMS installation, it's required to completely disassemble the firearm host. Please read safety precautions, listed below. Prior to disassembly, ensure that the firearm is clear and safe. Be sure to abide by all firearms safety rules.

*It is strongly advised that anytime you manipulate or make any modifications to your firearm, that a designated safe area is to be used. This area should be free of any live ammunition and loaded magazines. Be sure your firearm is clear and safe prior to disassembly or installation of new parts.

*All screws should be installed using the included thread locker and torqued to the specifications listed below. The over-tightening of any of the provided hardware could result in damage to the hardware or to the handguard itself.

1. Using the four included “Gas Tube Mounting Screws” attach the gas tube to the Upper Mount. The Upper Mount will have a slot cut on one end. This end should be oriented towards the receiver. (7/64” Hex - 10-15in/lb)

*If you do not intend on using the MMS Gas Tube, and instead are utilizing your factory gas tube and upper handguard, you may skip Step 1.

1. Install the Gas Tube Assembly onto your firearm by sliding it forward over the gas block and down. Ensure that your gas tube lever is up and in the “open” position.
2. Loosely install the Handguard onto the Lower Mount, using the four included “Handguard Mounting Screws”. DO NOT fully torque these screws until later in the installation process. Torquing the Handguard Mounting Screws prematurely will make it difficult to attach the Lower Handguard Assembly.
3. Ensure that the factory lower handguard retainer is locked in place on the barrel. Attach the Lower Handguard Assembly onto the firearm. Align Upper and Lower Assemblies, this might require pushing the gas tube forward (towards the gas block). Loosely attach the Upper and Lower Handguard Assemblies using the two provided “Upper Clamp Mounting Screws”.
4. At this time, you may torque the four Handguard Mounting Screws to the specification provided. (3/32 Hex - 15-20in/lb)
5. Using the bottom of your receiver as a reference, torque the two “Upper Clamp Mounting Screws” to the specification provided below. When installing these screws, ensure that you are applying torque equally to both sides. There will be a small gap between the Upper and Lower Mount visible when looking inside the Handguard. These gaps should be equal on both sides. (9/64” Hex - 20-25in/lb)
6. At this time, set your gas tube lever to the “locked” position.

Installation is now complete.

Compatibility Matrix (refer to definitions above)

We hope you find this information helpful in selecting and installing the NEW Modular Mounting System!!

For all inquiries, please utilize the Contact Form.

We appreciate your continued support,

-JMac Customs