AR-15 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.
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Brand
- AR-15 Build Kits and Assemblies - AT3 Tactical (24)
- AR-15 Build Kits & Assemblies - STNGR (8)
- AR-15 Build Kits and Assemblies - UTG (7)
- AR-15 Build Kits and Assemblies - Magpul (5)
- AR-15 Build Kits and Assemblies - Rosco Manufacturing (4)
- AR-15 Build Kits and Assemblies - Radical Firearms (4)
- AR-15 Build Kits and Assemblies - LBE Unlimited (4)
- AR-15 Build Kits and Assemblies - Bravo Company (4)
- AR-15 Build Kits and Assemblies - Spike's Tactical (3)
- AR-15 Build Kits and Assemblies - Sons of Liberty Gun Works (3)
- AR-15 Build Kits and Assemblies - Midwest Industries (3)
- AR-15 Build Kits and Assemblies - Troy Industries (2)
- AR-15 Build Kits & Assemblies - Luth-AR (2)
- AR-15 Build Kits and Assemblies - TacFire (1)
- AR-15 Build Kits and Assemblies - Hogue (1)
- AR-15 Build Kits and Assemblies - Fortis (1)
- AR-15 Build Kits and Assemblies - CMMG (1)
- AR-15 Build Kits & Assemblies - B5 Systems (1)
- AR-15 Build Kits And Assemblies - Aero Precision (1)
- AR-15 Build Kits and Assemblies - 2A Armament (1)
Caliber
- AR-15 Build Kits and Assemblies - .223/5.56 (30)
- AR-15 Build Kits and Assemblies - .300 Blackout (5)
- AR-15 Build Kits and Assemblies - 9mm (5)
- AR-15 Build Kits and Assemblies - 6.5 Grendel (4)
- AR-15 Build Kits and Assemblies - 7.62x39 (3)
- AR-15 Build Kits and Assemblies - 224 Valkyrie (2)
- AR-15 Build Kits and Assemblies - 22 LR (2)
- AR-15 Build Kits and Assemblies - 350 Legend (2)
- AR-15 Build Kits and Assemblies - 450 Bushmaster (2)
- AR-15 Build Kits and Assemblies - 458 Socom (2)
- AR-15 Build Kits and Assemblies - 6.8 SPC (2)
- AR-15 Build Kits and Assemblies - 6mm ARC (2)
Color
- AR-15 Build Kits and Assemblies - Black (46)
- AR-15 Build Kits and Assemblies - Flat Dark Earth (43)
- AR-15 Build Kits and Assemblies - OD Green (35)
- AR-15 Build Kits and Assemblies - Burnt Bronze (20)
- AR-15 Build Kits and Assemblies - Titanium (19)
- AR-15 Build Kits and Assemblies - Tungsten (19)
- AR-15 Build Kits and Assemblies - Gray (18)
- AR-15 Build Kits and Assemblies - Pink (18)
- AR-15 Build Kits and Assemblies - Red (17)
- AR-15 Build Kits & Assemblies - Blue (3)
- AR15 Build Kits And Assemblies - Stainless (2)
- AR-15 Build Kits & Assemblies - Coyote Brown (1)
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RECOMMENDEDNEW
STNGR 16″ .223 Wylde Complete Upper Receiver w/ 15″ VYPR® Handguard, BCG & CH
STNGR Complete .223 Wylde Upper with VYPR Handguard The VYPR complete upper from STNGR has everything you need to take a complete lower to a full rifle fast. Perfect for...3 Options3 Options3 Options -
RECOMMENDEDNEW
STNGR 16″ .223 Wylde Complete Upper Receiver w/ 15″ VLCN® Handguard, BCG & CH
STNGR Complete .223 Wylde Upper with VLCN Handguard The VLCN complete upper from STNGR has everything you need to take a complete lower to a full rifle fast. Perfect for...3 Options3 Options3 Options -
RECOMMENDEDNEW
STNGR 16″ .223 Wylde Complete Upper Receiver w/ 15″ RPTR® Handguard, BCG & CH
STNGR Complete .223 Wylde Upper with RPTR Handguard The RPTR complete upper from STNGR has everything you need to take a complete lower to a full rifle fast. Perfect for...3 Options3 Options3 Options -
AT3™NEW
AT3™ AT-15 M-LOK Receiver Set – Anodized and Cerakote
https://www.youtube.com/watch?v=ufCPWjxhJ2Q AT3 Tactical AR-15 M-LOK Receiver Set Get your custom Cerakote AR build started with the sleek AT3 Tactical M-LOK Receiver set. This kit includes the new AT-15 Lower Receiver...24 Options -
AT3™NEW
AT3™ AT-15 Lower and Upper Receiver Set – Anodized and Cerakote
https://www.youtube.com/watch?v=ufCPWjxhJ2Q AT3 Tactical AR-15 Stripped Cerakote Upper and Lower Set The AT-15 Receiver Set includes a stripped lower and upper, in 7 Cerakote shades plus classic anodized black. This kit...8 Options8 Options8 Options -
AT3™NEW
AT3™ AT-15 Quad Rail Receiver Set – Anodized and Cerakote
https://www.youtube.com/watch?v=ufCPWjxhJ2Q AT3 Tactical AR-15 Cerakote Quad Rail Receiver Set Start your next AR build build with a rock solid foundation, and ready for your custom touch with Cerakote or anodized...32 Options32 Options32 Options -
AT3™NEWUpgrade Sale!
AT3 Tactical AR-15 Ultimate Cerakote Color Upgrade Kit
Cerakote Color Accent Parts Kit with Buffer Tube and Ambi Safety The Ultimate Cerakote Color Upgrade Kit completely overhauls your lower receiver, from takedown pins to buffer tube. Enhance function...8 Options8 Options8 Options$99.99$89.99 -
AT3™NEWUpgrade Sale!
AT3 Tactical AR-15 Cerakote Color Upgrade Kit
Cerakote Color Accent Parts Kit Cerakote color parts for your AR-15 can enhance your build and help you stand out, or blend in. This Cerakote parts kit includes replacements for...8 Options8 Options8 Options$27.99$25.19 -
AT3™NEWUpgrade Sale!
AT3 Tactical AR-15 Enhanced Cerakote Color Upgrade Kit
Cerakote Color Accent Parts Kit with Dust Cover and Safety The Enhanced Cerakote Color Upgrade Kit includes a full set of lower parts for your AR-15, plus a matching Cerakote...8 Options -
AT3™NEW
AT3™ AT-15 M-LOK Receiver Set – Bright White Cerakote
AT3 Tactical White M-LOK Receiver Set - Limited Edition! Start a new Bright White AR-15 build with this limited run from AT3 Tactical! This AT-15 M-LOK Receiver set includes an... -
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 all parts individually! This furniture set contains 3 easy-to-install components - MOE...27 Options -
AT3™RECOMMENDEDUpgrade Sale!
AT3™ Pro-Builder™ AR-15 Lower Parts Kit – No Grip or Trigger Assembly
Perfect Lower Parts Kit for the Premium Builds This quality lower parts kit excludes the two most commonly upgraded components - the grip and the trigger assembly (fire control group)....10 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...27 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 -
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 -
Upgrade Sale!
Timber Creek Outdoors Small Parts Pack – Ambidextrous Safety, Extended Mag Release, and Takedown/Pivot...
Make Your Lower Unique and Easier to Use Complete your lower with style and enhanced ergonomics! Save money by bundling a unique Timber Creek Outdoors Ambidextrous Safety, Extended Magazine Release,...8 Options -
Magpul CTR Stock Kit | Furniture Kit for AR-15– CTR Stock, MOE+ Grip &...
Transform Your Rifle With The Magpul Premium Furniture Kit Save by bundling vs purchasing the parts individually! Exclusively from AT3 Tactical This Premium version of our popular, easy-to-install MOE furniture...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... -
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 -
RECOMMENDED
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... -
AT3™
AT3™ 2-Stage AR 15 Lower Parts Kit with Nickel Boron Trigger – No Grip...
Experience the difference a 2-Stage Trigger makes in your next build. AT3 is pleased to offer the dependability of our Pro-Builder Lower Parts kit with the 2-Stage Nickel Boron Trigger.... -
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 Options4 Options4 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