AR-15 Build Kits and Assemblies
Build Your Next Custom AR-15 with Quality Kits and Complete Assemblies
Find the right lower parts kits, upper receiver assemblies, and even complete rifle kits to make your next build truly your own! AT3 offers discounted bundles for gun builders, from lower parts kits with matching grips and stocks, to complete uppers with a variety of Cerakote finishes. READ MORE
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Magpul MOE M-LOK Furniture Kit – Stock, Carbine Handguard & Grip for AR 15
Customize the look and feel of your AR with a Magpul MOE Furniture Kit. Save 15% vs purchasing the parts individually, plus free shipping. This furniture set contains 3 easy-to-install...24 Options -
New
Aero Precision X15 Receiver Set – AR-15 Lower Receiver with Assembled Upper Receiver
Aero AR-15 Lower and Upper Receiver Set Aero Precision's X-15 receiver set makes a solid foundation for your next AR-15 build. This matching set of lower and upper receiver includes...4 Options -
AT3™
AT3 SPEAR Furniture Kit – AT3 AR 15 M-LOK Handguard, Magpul MOE Stock &...
Accurize and customize your AR with an AT3 Free-Float Rail and matching Magpul furniture! Save by bundling vs purchasing the parts individually, plus free shipping. This furniture set contains 3...24 Options -
AT3™
AT3™ Mil-Spec AR-15 Buttstock Kit – Stock, Buffer, Tube, Springs, Plate
This buttstock kit combines a Mil-Spec stock and buffer tube with all the needed parts to complete your build. This Mil-Spec Buttstock AR-15 Buttstock Kit includes the buttstock, buffer tube,... -
Magpul CTR Stock Kit | Furniture Kit for AR-15– CTR Stock, MOE+ Grip &...
Transform Your Rifle With The Magpul Premium Furniture Kit Save over 15% vs purchasing the parts individually, plus free shipping. Exclusively from AT3 Tactical This Premium version of our popular,...12 Options -
UTG Pro Six Position Mil-spec AR 15 Buffer Tube Kit
Complete UTG Buffer Assembly - Add Your Own Stock This receiver extension kit from UTG comes with a buffer tube, buffer spring, 3.0 oz carbine buffer, castle nut, and endplate. ...2 Options -
UTG Pro AR-15 Ops Ready S4 Mil-Spec Stock Kit – Buffer Assembly Included
Compact AR-15 Stock Kit for CQB and PDWs The two-piece S4 stock comes with a complete set of all the parts you'll need for finishing off your AR-15's recoil system. ...2 Options -
New
B5 Systems Bravo AR-15 Furniture Kit – Stock, Carbine M-LOK Handguard, and Pistol Grip
B5 Systems Furniture Kit for AR-15 B5 Systems makes some of the toughest, most ergonomic parts on the market. And you can easily upgrade your AR-15 with three components from...4 Options -
Magpul MOE SL Furniture Kit | AR 15 Stock, Grip & M-LOK Handguard
Stand out from the crowd - Upgrade your AR-15 with the Magpul MOE SL™ Slim Line Furniture Kit Save over 15% vs purchasing the parts individually, plus free shipping. Exclusively...12 Options -
CMMG A1 Style Rifle Length AR 15 Stock Kit – Buffer Parts Included
The CMMG A1 Stock Kit - Classic and Dependable When the AR-15 was first introduced, it shipped with the A1 stock. This modern replica by CMMG captures all of the... -
UTG A2 Fixed AR 15 Rifle Stock Assembly – All Parts Included – Buffer,...
Highly Recommended Rock Solid Fixed Stock - Tough Finish, Easy to Install This is a complete kit that includes a 4.8-ounce buffer, action spring, receiver extension, stock, butt plate, stock... -
LBE Unlimited AR-15 Low Profile .750 Gas Block with Assembled Gas Tube
Pre-Installed Gas Block and Tube from LBE Unlimited Remove the hassle of trying to pin the gas block and gas tube for your AR-15 with this pre-assembled package from LBE...4 Options -
UTG PRO 6-Position Mil-spec AR 15 Stock Kit – All Parts Included – Buffer,...
UTG PRO 6-Position Mil-spec Stock Kit - All Parts Included - Buffer, Tube, Springs, & More Proudly Made in USA Polymer Stock Made from Impact Resistant High-strength Material Mil-spec Diameter...2 Options -
AT3™
AT3 AR 15 Lower Build Kit – Magpul Stock and Grip, AT3 Lower Parts...
Finish Off Your New Rifle Lower with an Enhanced Trigger and Matching Magpul Furniture Your AR lower has some of the most critical parts you don't want to skimp on...4 Options -
AT3™
AT3™ FF-ML 11.5″ Complete AR 15 Pistol Upper – .223/5.56 11.5″ Ballistic Advantage Barrel...
Uncompromising quality meets unbeatable value - The AT3 11.5" Pistol Upper with SPEAR M-LOK Handguard AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality Where it...8 Options -
AT3™
AT3™ FF-ML 10.5″ Complete AR 15 Pistol Upper – Choose Your Own 10.5 inch...
Uncompromising quality meets unbeatable value - The AT3 10.5" Pistol Upper with SPEAR M-LOK Handguard AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality Where it...16 Options -
UTG PRO S3 Mil-Spec AR 15 Buttstock Kit – All Parts Included – Buffer,...
UTG PRO S3 Mil-Spec Buttstock Kit - All Parts Included - Buffer, Tube, Springs, & More Built for Heavy-duty Use with the Tightest Tolerance Controls to Provide the Most Secure...2 Options -
Real Avid AR-15 Master Bench Block
Magnetic AR-15 Bench Block for Bolt, Upper, Lower, and More The Master Bench Block acts as a second pair of hands when assembling and disassembling your rifle. This tough block... -
TacFire RK556 Unassembled AR-15 Complete Rifle Kit
Unassembled Rifle Kit with Free-Float Handguard Build a complete AR-15 that can do it all at an excellent price point with Tacfire. This kit ships to your door unassembled, with... -
LBE Unlimited Buffer Tube for AR-15 – MILBUFKT
LBE Complete AR-15 Mil-Spec Buffer Tube Kit The LBE Unlimited Mil-Spec Buffer Tube Kit for the AR15 comes with a buffer tube, castle nut, lock plate, recoil buffer and recoil...4 Options -
AT3™
AT3™ FF-ML 11.5 Inch Complete AR 15 Pistol Upper – .223/5.56 11.5 Inch Faxon...
AT3's Best Pistol Upper - Featuring an Adjustable Midlength Gas System on an 11.5" Faxon Firearms Barrel AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality...8 Options -
BCM MK2 Recoil Mitigation System Mod1 for AR-15
Recoil Reducing AR-15 Buffer Kit Bravo Company's MK2 Recoil Mitigation System effectively reduces recoil with a few changes to key components. This kit uses a longer, 8 position buffer tube,...3 Options -
AT3™
AT3™ FF-ML Complete Rifle AR 15 Upper – .223/5.56 16″ Faxon Firearms Barrel –...
Uncompromising quality meets unbeatable value. The AT3 Tactical FF-ML Complete AR-15 Upper, now with a lightweight Faxon Gunner barrel! AT3 Complete Upper assemblies are Built for Accuracy and Reliability -...16 Options -
UTG PRO S2 Mil-Spec AR 15 Buttstock Kit – All Parts Included – Buffer,...
UTG PRO S2 Mil-Spec Buttstock Kit - All Parts Included - Buffer, Tube, Springs, & More Built for Heavy-duty Use with the Tightest Tolerance Controls to Provide the Most Secure...2 Options
Other Other AR-15 Parts & Accessories:
All Other Products
AR 15 Furniture Kits
AR-15 Cleaning Kit and Tools
AR-15 Conversion Kits .22 LR and More
AR-15 Rifle Bipods
AR-15 Slings & Mounts
AR-15 Upper: Complete Upper Assemblies
Rifle Cases for AR-15
AR-15 Build Kits and Assemblies
AT3 Swag
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