MSF 3” 9mm Pistol Build Kit



Upper Options

Customize your upper receiver using the options below

Free Shirt with build kit purchase?

Free Retro-Rifle Shirt With Purchase of Ar15 Build Kit or rifle

Charging Handle Options


Lower Options

Customize your lower receiver using the options below

End Plate

Pistol Brace/Buffer Tube Options *

Pistol Grip Options

m4 / ar15 / m16 polymer pistol grip
Magpul MOE® Grip – AR15/M4 , black $19.95
MOE-K2® Grip – AR15/M4 - Magpul FDE $20.95
17 Degree Pistol Grippy Grip - AR15 $9.95
Key100 Rubberized Polymer Ar15 pistol grip, black $9.99
Key101 Ar textured pistol grip $9.99

Takedown/Pivot Pins

Trigger/Hammer Pins

Safety Selector


Foregrip Options

Optic Options

Light Options

Folding Adapter

Lower Parts ?

Ar15 Standard Lower Parts Kit LPK $49.99
Velocity 3lb Enhanced AR-15 Lower Parts Kit LPK $199.00
Ar15 Mil Spec Carbine Buffer Tube Kit $39.99


SPIRITUS Systems SIERRATAC Padded Sling - ranger-green $59.99
SPIRITUS Systems SIERRATAC Padded Sling - wolf-grey $59.99
SPIRITUS Systems SIERRATAC Padded Sling - multicam-tropic $59.99
SPIRITUS Systems SIERRATAC Padded Sling - black $59.99
SPIRITUS Systems SIERRATAC Padded Sling - multicam-black $59.99
SPIRITUS Systems SIERRATAC Padded Sling - coyote-brown $59.99
SPIRITUS Systems SIERRATAC Padded Sling - multicam-arid $59.99
SPIRITUS Systems SIERRATAC Padded Sling - multicam $59.99
SPIRITUS Systems SIERRATAC Padded Sling - woodland $59.99

Tools / Extras

Product price: $399.00
Order total:

Free shipping on all orders over $500

Includes flash can as a muzzle device.

This build kit includes everything you need to complete your stripped lower into a functioning firearm.  The upper will be fully assembled and test fired.  The lower components can easily be assembled into your receiver.  Use the takedown pins to attach the two components, and you are good to go!  Be sure to scroll through the options and select parts to best fit your needs and make your weapon unique.

Assembled, Test-Fired and QC’d In-House

We assemble everything in-house, completely customized to your order. Our engineers have many years of experience in the industry, making sure that everything that goes out the door is built to the highest standard possible.

Prior to shipping, we test fire and follow a strict quality control protocol, paying extra attention to the gas system and headspace, ensuring that your AR-15 will function properly and will reliably fire in all cases. 

High-Quality Components

Over the past 10 years, we have carefully refined the parts we use for our AR-15 build kits. We only use high-quality components in our builds that have been sourced from proven manufacturers and OEMs.

We have built tens of thousands of AR-15s and ensure reliability, durability, and accuracy in all of our products.

Limited Lifetime Warranty

We stand behind our products and have a limited lifetime warranty on the build kits that we sell.  Our warranty protects against defects in product, material, or workmanship.

If there is an issue, simply contact us, and we will handle it. We will repair/replace items if necessary. 

Additional information

Weight 5 lbs
Barrel Size