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  • Classic Lower Build Kit | Classic Lower Parts Kit | Butt Stock | Buffer Tube Assembly | AR-15

    Classic Lower Build Kit | Classic Lower Parts Kit | Butt Stock | Buffer Tube Assembly | AR-15

    $74.99

    No 80% lower receiver build is complete without all its components. This LPK comes with everything you need: A lower parts kit, butt stock, and buffer tube assembly. All parts are US-made and CNC machined for precision fitment. All trigger components are mil-spec. This Lower Parts Kit Includes: Hammer Pistol Grip Trigger Pivot & Takedown…

  • LR-308/AR-10 Lower Parts Kit (w/ Hammer and Trigger)

    LR-308/AR-10 Lower Parts Kit (w/ Hammer and Trigger)

    $54.99

    We strive to provide accurate photographs of our product. Due to parts availability, this kit’s trigger and hammer may come in stainless or black. Want an LR-308 trigger that suffers no creep, take-up, or over-travel? Looking for the easiest-to-install LPK? How about the most affordable parts kit possible? This LR-308 LPK comes in at a…

  • Adjustable Carbine Stock & Buffer Tube Assembly

    Adjustable Carbine Stock & Buffer Tube Assembly

    $39.99

    Whether you bought stripped lower, or just finished an 80% lower, you’ll need two components to assemble it and make it functional: A lower parts kit, and a buffer tube assembly like this one. Buffer tube assemblies work with your lower parts kit, allowing your lower and upper receivers to work together. What’s Included Buffer…

  • AR-15 Bolt Carrier Group (Full Auto Profile) - .223 / 5.56mm NATO / .300 AAC Blackout

    AR-15 Bolt Carrier Group (Full Auto Profile) – .223 / 5.56mm NATO / .300 AAC Blackout

    $67.99

    Precision-machined (and upgraded) in the U.S.A. Our M16-profiled bolt carrier group is manufactured using properly heat-treated 8620 and 9310 tool steel, affording identical performance and reliability to units with C158 bolts at a much lower price. Each bolt and carrier receives quality gas seals on every bolt. Extractors are upgraded to S7 tool steel, affording…

  • Mil-spec AR-15 Buffer Tube Assembly

    Mil-spec AR-15 Buffer Tube Assembly

    $29.99

    This stock-less Buffer Tube Assembly is perfect if you’re completing an AR pistol, or if you bought a custom or upgraded stock for your rifle build. This kit includes all other buffer components needed to work with your lower parts kit and upper assembly. What’s Included Buffer Tube Carbine Buffer Recoil Spring Castle Nut Latch…

  • Mil-Spec AR15 Lower Parts Kit (w/ Hammer and Trigger)

    Mil-Spec AR15 Lower Parts Kit (w/ Hammer and Trigger)

    $39.99

    Want an AR-15 trigger that suffers no creep, take-up, or over-travel? Looking for the easiest-to-install LPK? How about the most affordable parts kit possible? This mil-spec AR-15 LPK comes in at a great price with machining and performance that feels match-grade. Polished for Performance Inside this kit, you’ll find a disconnector, hammer hook, and sear…

  • SBA3 Pistol Stabilizing Brace by SB Tactical (5-Position, Black)

    SBA3 Pistol Stabilizing Brace by SB Tactical (5-Position, Black)

    $119.99

    Let’s face it: just having a bare buffer tube or pistol tube on the end of your pistol build makes your pistol look like it skipped leg day at the gym? Slap a proper pistol brace on there and enjoy better accuracy and comfort with the SBA3 Pistol Stabilizing Brace by SB Tactical. This SBA3…

  • Sale! ALG Defense QMS Quality Mil-Spec Trigger

    ALG Defense QMS Quality Mil-Spec Trigger

    Original price was: $68.25.Current price is: $54.97.

    Some of us like our AR platform rifles traditional or built as close to mil-spec as possible. We build replicas of that Colt model 629 or of the old-school M-16, because we want that nostalgia when we shoot. There’s just one problem: the mil-spec triggers of these rifles of a bygone era were gritty and…

  • Mil-spec AR-15 Butt Stock

    Mil-spec AR-15 Butt Stock

    $13.99

    The original M4-type buttstock. Aftermarket stocks are awesome, but some builders prefer the good ole’ mil-spec stuff. This M4 six-position buttstock perfectly replicates the stock found on service-issued rifles. It’s made from the same injection-molded polymer and sports a six-position-adjustable latch for dialing in length of pull. M4 Stock: Mil-Spec Fitment (1.148″ OD) This “M4″…

  • Mil-spec AR-15 Charging Handle

    Mil-spec AR-15 Charging Handle

    $11.99

    This mil-spec AR-15 charging handle will complete any mil-spec standard-sized AR-15 rifle build. It’s black and made from 6061 T6 billet aluminum. Features: Made from 6061 T6 billet aluminum Mil-spec dimensions For use with standard-sized AR-15 rifles  

  • Lower Receiver Set Screw and Roll Pin Screw Replacement Set

    Lower Receiver Set Screw and Roll Pin Screw Replacement Set

    $7.99

    This kit contains replacement threaded components that come with Premium 80% Lowers (Fire/Safe Marked Billet) and AR-9 (9MM) 80% Lowers (Billet). These receivers feature upgraded bolt catch and takedown detent fittings. Both fittings are threaded. A 1/16 sized hex key will work for both set screws.  Replacement Set Includes: 1 x 6/32″ Bolt Catch Roll…

  • .300 Blackout AR 15 Pistol Upper Assembly - 7.5" Parkerized Heavy Barrel, 1:8 Twist Rate w/ 5.5" M-LOK Handguard

    .300 Blackout AR 15 Pistol Upper Assembly – 7.5″ Parkerized Heavy Barrel, 1:8 Twist Rate w/ 5.5″ M-LOK Handguard

    $259.99

    Optimized for subsonic accuracy. Featuring a 7.5″ heavy barrel with a 1:8 twist rate, this 300 Blackout AR-15 upper provides the perfect combination of parts and specifications to ensure all subsonic loads are stabilized for maximum accuracy. Included is an upgraded, custom billet upper with a side-charging bolt carrier group for improved ergonomics. What’s Included…

  • .308 Dust Cover / Ejection Port Cover Assembly

    .308 Dust Cover / Ejection Port Cover Assembly

    $7.99

    US-made. Includes dust cover, rod, and spring. A simple, quality .308 dust cover for finishing your custom, stripped .308 upper receiver. Fits all DPMS-patterned LR-308 / AR-10 receivers. Made from billet (6061-T6) aluminum, and finished with a mil-spec anodized finish to match virtually all anodized black receivers in color and finish.    

  • Sale! 1911 AR Pistol Grip

    1911 AR Pistol Grip

    Original price was: $64.99.Current price is: $19.97.

    Give Your AR the 1911 Treatment. These are real, bona fide 1911 grips, complete with standard grip panel threaded inserts, made specifically for the AR platform! Anodized and available in Black, Gray, or OD Green, these grips are incredibly strong and lightweight, while improving ergonomics by offering a more vertical grip angle. Note: Grip panels…

    Select optionsLoading Done This product has multiple variants. The options may be chosen on the product page
  • 5.56 AR 15 Upper Assembly - 16" Parkerized Barrel, 1:8 Twist Rate with 15" Talon M-LOK Handguard

    5.56 AR 15 Upper Assembly – 16″ Parkerized Barrel, 1:8 Twist Rate with 15″ Talon M-LOK Handguard

    $299.99

    So half-way done with building your own AR-15. You’ve gotten as far as building the bottom half, and you’re now ready to tackle your upper assembly. Think of it this way: you’re not half-way done, you’re damn near completely done. Because if you can turn a screwdriver, allen wrench, or socket wrench to install backup…

  • Sale! 7.62x39 AR 15 FDE Cerakote Upper Assembly - 16" Parkerized Heavy Barrel, 1:10 Twist Rate with 15" Talon M-LOK Handguard

    7.62×39 AR 15 FDE Cerakote Upper Assembly – 16″ Parkerized Heavy Barrel, 1:10 Twist Rate with 15″ Talon M-LOK Handguard

    Original price was: $369.99.Current price is: $339.97.

    Engineered for precision and power, this 7.62×39 AR-15 upper combines a heavy barrel with the 7.62×39 cartridge, offering superior performance long missing from other rifles. Built around a 16″, 1:10-twist, heavy barrel housed within a custom free-float M-LOK handguard, this upper offers tighter shot groups and improved heat resistance during rapid fire. This upper features…

  • Sale! 7.62x39 AR 15 Tungsten Cerakote Upper Assembly - 16" Parkerized Heavy Barrel, 1:10 Twist Rate with 15" Talon M-LOK Handguard

    7.62×39 AR 15 Tungsten Cerakote Upper Assembly – 16″ Parkerized Heavy Barrel, 1:10 Twist Rate with 15″ Talon M-LOK Handguard

    Original price was: $369.99.Current price is: $339.97.

    Tungsten Cerakote 7.62×39 AR-15 Upper with 16″ Heavy Barrel and 15″ Talon M-LOK Handguard Want to shoot 7.62×39 without switching platforms? This upper puts the classic AK cartridge on your AR-15 lower, and its 16″ heavy-profile barrel stands up to long strings of fire while keeping your groups consistent. The handguard and forged upper receiver…

  • Sale! Adjustable Carbine Stock & Buffer Tube Assembly for LR-308/AR-10

    Adjustable Carbine Stock & Buffer Tube Assembly for LR-308/AR-10

    Original price was: $39.99.Current price is: $34.99.

    No LR-308 80% lower receiver build is complete without a buffer kit. In combination with a lower parts kit (sold separately), this kit includes all components necessary to finish assembling your .308 lower receiver. What’s Included Buffer Tube .308 Buffer Recoil Spring Castle Nut Latch Plate Adjustable Stock Mil-Spec / Standard Buffer Fitment This buffer…

  • Sale! Aero Precision Delta 556 Muzzle Brake

    Aero Precision Delta 556 Muzzle Brake

    Original price was: $59.99.Current price is: $37.97.

    Love the original A2 flash hider? Wish it was even better? Need a lil’ extra length? That’s where Aero Precision’s Delta 556 Muzzle Brake comes in. Drawing from the original M16 flash hider’s design, this extended muzzle brake further reduces muzzle rise and muzzle flash, keeping your point of aim unobstructed and allowing for quicker,…

  • Sale! AR 10 / LR-308 "Birdcage" Flash Hider (5/8x24 Threads)

    AR 10 / LR-308 “Birdcage” Flash Hider (5/8×24 Threads)

    Original price was: $6.99.Current price is: $4.97.

    A standard, A2-style flash hider for your AR 10 / LR-308 rifle. Features standard 5/8×24 TPI threads for universal compatibility with .30-caliber, AR-type barrels. Made from solid 4150 steel with a matte Parkerized finish. Features classic “A2”-style, five-slot pattern with solid bottom to reduce muzzle rise and flash.  

  • Sale! AR 15 Dust Cover (Aluminum)

    AR 15 Dust Cover (Aluminum)

    Original price was: $6.99.Current price is: $2.99.

    Quality, US-made AR-15 dust cover assembly. AND it’s the CHEAPEST! Period! This mil-spec AR 15 dust cover includes a rod and spring for installation. The cover is finished with a standard black anodized coating, ensuring it matches all standard, stripped AR-15 upper receivers in color and finish.

  • AR-10 Bolt Carrier Group - .308/6.5 Creedmoor/.243 Winchester

    AR-10 Bolt Carrier Group – .308/6.5 Creedmoor/.243 Winchester

    $89.99

    So you just built a larger-sized AR chambered in either .308 Winchester, 6.5 Creedmoor, or even .243 Winchester, but you know what? Unless you want it to be nothing more than a replica or a life-sized prop, you’re gonna need to install the guts too, to get it to function. The “guts” of the upper…

  • Sale! AR-15 Pistol Lower Build Kit w/ No Brace

    AR-15 Pistol Lower Build Kit w/ No Brace

    Original price was: $69.99.Current price is: $64.99.

    A no-brace lower build kit for your custom AR-15 pistol. This lower build kit is the perfect affordable choice for completing your AR-15 pistol build. It includes a mil-spec LPK and buffer kit with no pistol brace nor buttstock. Add your own brace later, or just run it slick. Classic Lower Parts Kit This Classic…

  • Sale! AR-15 Pistol Lower Build Kit w/ SBA3 Brace

    AR-15 Pistol Lower Build Kit w/ SBA3 Brace

    Original price was: $189.99.Current price is: $179.99.

    The original mil-spec AR-15 lower build kit. Includes the O.G. pistol brace, the SBA3 from SB Tactical. This mil-spec lower build kit includes the parts you need to assemble your stripped lower receiver, completing the “lower half” of your custom AR-15 pistol build. Classic Lower Parts Kit This Classic LPK features a mil-spec hammer and…

  • AR-9 Bolt Carrier Group (Nitride) - 9mm

    AR-9 Bolt Carrier Group (Nitride) – 9mm

    $109.99

    You’ve meticulously picked out the parts needed for your new AR9 upper, and now you need  that final piece that is going to breathe some life into. Made in the USA, this AR9 Bolt Carrier Group is machined from 8620 Steel that ensures a high durability and longevity and features an enhanced firing pin as…

  • AR15 Forward Assist Assembly

    AR15 Forward Assist Assembly

    $9.99

    Mil-spec AR15 forward assist assembly. Includes forward assist, spring, and roll pin.

  • Sale! AR15 Low-Profile Gas Block - .750"

    AR15 Low-Profile Gas Block – .750″

    Original price was: $14.99.Current price is: $11.97.

    Every gas-operated AR (those that don’t employ a piston system) needs a gas block of some type to cycle between shots. If you’re building an old-school or retro style AR, it may have a fixed front sight that doubles as the gas block or some fold-up variant thereof. But if it’s any number of countless…

  • AR15 LPK - Basic Build Kit

    AR15 LPK – Basic Build Kit

    $27.99

    The Kak Industry AR15 Lower Parts Kit comes with all of the basic essentials you’ll need for your own custom AR15 build. This build kit includes the following: bolt catch kit magazine catch kit hammer & trigger pins pivot pin & detent & spring buffer retainer pin & spring takedown pin & detent spring safety…

  • AR15 LPK Missing Parts Kit

    AR15 LPK Missing Parts Kit

    $11.99

    This AR15 LPK Missing Parts Kit has all the essentials for any lost parts, replacement parts, or for your next custom build. All parts are proudly made in the USA. This LPK Missing Parts Kit comes with: (1) buffer retainer (1) buffer retainer spring (1) bolt catch detent (2) bolt catch springs (2) selector detents…

  • Sale! AR15 Pin & Detent Parts Kit

    AR15 Pin & Detent Parts Kit

    Original price was: $19.99.Current price is: $16.97.

    The KAK Industry AR15 Pin & Detent Parts Kit is made out of the best parts on the market. This kit is great for replacement parts, a new build, or having spare parts. This kit includes: a pivot pin takedown pin pivot and takedown detents hammer and trigger pin bolt stop plunger bolt stop roll…

  • Sale! AR15 Tapered Steel Crush Washer 1/2"x28

    AR15 Tapered Steel Crush Washer 1/2″x28

    Original price was: $1.59.Current price is: $0.97.

    If you plan to go the traditional (and the easiest) route with the business end of your .223 or 5.56mm chambered AR by installing a muzzle device, you’ll need a crush washer. This is that crush washer. You simply slide it onto the threading of your barrel, tapered end first, crowned end facing out, screw…

  • AR9 Ejector Plate and Mag Release Kit

    AR9 Ejector Plate and Mag Release Kit

    $24.99

    This is a replacement ejector plate and magazine release kit for our AR9 80% Billet Lower Receiver. Ejector Plate Specifications: Made from 17-4 Stainless Steel hardened to RC42 2 cap screws included Mag Release Specifications: Billet aluminum magazine catch Dowel pin, spring and set screw included Lower receiver not included.  

Quality AR parts kits, triggers, receivers, handguards, BCGs, and AR-15 accessories.
Welcome to the parts counter. Ready to build a truly custom AR-15 from scratch? It’s all here: Upper parts, lower parts, rail attachments, grips, handguards — you name it, we’ve got it.
Need help picking parts? Start with our Builder’s Master Guide.
AR Lower Parts: What’s in a Receiver?
We’ve sourced quality, mil-spec lower receiver internals and components so you can complete your AR-15 build with confidence backed by guaranteed compatibility. The AR lower parts assembly includes the following:

Stripped lower receiver, or fabricated 80% Lower
Lower parts kit
Buffer tube
Buffer and recoil spring
Pistol grip
Castle nut
Latch plate

Grips, castle nuts, and latch plates are typically included in the lower parts kit. An upgraded latch plate (like this Magpul ASAP QD plate) includes a QD sling stud mount for easy carrying. An upgraded drop-in or “cassette” trigger (like this JMT Single Stage) provides a better trigger pull with less weight and faster, smoother resets for improved accuracy.
Ready to assemble? Here’s how to install your lower parts kit.
Not sure what parts you need? Check out our full lower assemblies!
AR Upper Parts: Everything You Need
Your finished AR upper is the “business end” of your rifle or pistol: It’s responsible for chambering and firing live rounds. So, you’re going to want the highest-quality parts for reliability and accuracy. That means investing in a 4150 CMV barrel, an M16-type bolt carrier group, and a forged M4-type upper receiver. We’ve got all those components available at great prices.
Want to make it even easier? We’ve got tons of barreled upper assemblies, pre-built with a bolt included, ready for install. Options are available for .308, 6.5 Creedmoor, .223 Wylde, 300 Blackout, and 9mm, and of course, 5.56 NATO.
Here’s how to install the AR-15’s barrel, gas system, and handguard.
Grab Your Gunsmithing Tools, Too!
Ever try to install an LPK without punches? You probably wound up losing some of those tiny roll pins, halting your build. Get rid of the frustration and guesswork and grab the tools you need to confidently attack your 80% project. We’ve got quality Armorer’s Wrenches, torque wrenches, roll pin kits, vise blocks, and all the other gunsmithing tools you need to go from a hunk or aluminum or polymer to a locked n’ loaded shooter. Grab a complete Armorers Kit like the Wheeler set, and you’ll have virtually all the tools required.
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