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 -
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,... -
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 -
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 -
Magpul MOE SL | 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 -
AT3™
KAK Shockwave Blade AR-15 Pistol Brace Kit – Blade, Custom Pistol Buffer Tube, Buffer,...
This kit includes everything you need to set up and add the KAK Shockwave to your AR pistol! Kit contains a black KAK Shockwave Blade, an AT3 custom buffer tube...4 Options -
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... -
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... -
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...12 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 -
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™ 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...24 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 -
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...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... -
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 -...24 Options -
AT3™
AT3 AR 15 Pistol Lower Build Kit – KAK Pistol Brace, Magpul Grip, AT3...
Finish Your New Pistol Lower the Right Way - In the Color You Want! Have a vision for completing your next AR lower? Want to save a little cash without...4 Options -
AT3™
AT3™ FF-ML 10.5 Inch .300 Blackout Pistol Upper for AR-15 – 12″ M-LOK Free...
Uncompromising quality meets unbeatable value - The AT3 10.5" .300 BLK Pistol Upper with SPEAR M-LOK Handguard AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality...12 Options -
AT3™
AT3™ FF-ML 10.5 Inch Complete PCC AR 15 Upper – 9mm 10.5 Inch Faxon...
Pistol Caliber, Pistol Configuration - The Foundation of a Great 9mm Subgun AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality Where it Counts - premium...12 Options -
AT3™
AT3™ FF-ML 16 Inch .300 BLK Complete AR 15 Upper – .300 AAC Blackout...
Uncompromising quality meets unbeatable value - The AT3 16" .300 BLK Rifle Upper with SPEAR M-LOK Handguard AT3 Complete Upper assemblies are Built for Accuracy and Reliability - Guaranteed. Quality...12 Options -
AT3™
AT3™ FF-ML 16 Inch Complete AR 15 PCC Upper – 9mm 16 Inch Faxon...
The competitive edge you need for your Pistol Caliber Carbine - ready for your Glock or Colt style lower AT3 Complete Upper assemblies are Built for Accuracy and Reliability -...12 Options -
AT3™
AT3™ Complete Rifle Kit – Magpul Lower Build Kit – .223/5.56 16 Inch Ballistic...
Instant Rifle. Just Add Lower. Don't settle for the budget-line rifle kits you're used to seeing. Get a complete assembled upper from AT3 Tactical, with a lower build kit including...16 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
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
