We Ship Fast!
Order by 1PM CST for Same Day Shipping (Mon-Fri)
AT3™ FF-KM Complete Rifle Upper – .223/5.56 16″ Ballistic Advantage Barrel – Keymod Free Float Handguard
Lifetime WarrantyOn All AT3 Brand Products
All AT3 Tactical Brand Products carry a lifetime warranty against manufacturer’s defects.
This includes AT3 Red Dot Sights, Handguards, Iron Sights, and any other product that carries the “AT3 Tactical” or “AT3™” name. For other brands (ex. Magpul or Troy), please refer to the manufacturer’s warranty policy.
In the event that your AT3™ product becomes unusable, we will repair or replace the product at no charge to you.
If we cannot repair your product, we will replace it with a product in perfect working order of equal or better physical condition. The warranty is fully transferable, but we may require information about the original purchase to validate the authenticity of the product.
If your product is in need of warranty service, please contact AT3 Tactical to start the process
Our contact info is available here. To expedite processing, please provide your order information and description of the defect.
Please note: The AT3 Lifetime Warranty does not cover loss, theft, intentional damage or cosmetic damage that doesn’t affect the performance of the product.
Fast & Free Shipping On orders over $50
You will receive fast, free shipping for all orders over $50
Shipping cost is $7.99 for orders under $50. We ship with UPS or USPS, depending on the item.
Most orders received by 1pm CST ship the same day
You will receive an email with tracking information at the time of shipment. To expedite shipping, we may ship your order from multiple warehouses. Orders placed on weekends, holidays, or after 1pm will ship the following business day.
Uncompromising quality meets unbeatable value. The AT3 Tactical FF-KM Complete AR-15 Upper.
AT3 Complete Upper assemblies are Built for Accuracy and Reliability – Guaranteed.
- Quality Where it Counts – premium components like Ballistic Advantage barrels, Aero Uppers, and AT3 handguards. Don’t settle for “bargain uppers” with unknown components.
- Guaranteed Reliability– Test-fired before shipment to assure proper function, and backed by the AT3 Lifetime Warranty
- Unbeatable Value – Unbeatable quality in the price range. Save up to 20% off vs purchasing the components separately.
This fully assembled AR-15 complete upper includes:
16″ Ballistic Advantage 1:7 4150 CMV M4 Nitride Barrel (with low profile gas block & carbine gas tube)
Ballistic Advantage Modern Series barrels feature precision-machined 4150 CMV steel, durable QPQ (Nitride) coating, and a Sub-MOA accuracy guarantee.
AT3 PROMOD-K Free Float Keymod handguard (choose length with dropdown menu)
Unique lightweight, slim design with Keymod attachment points. Rock-solid 6061 aircraft aluminum handguard that withstands the harshest treatment. One 5-slot Keymod-to-Picatinny rail section included.
Forged from 7075-T6 aluminum, this assembled upper is precision machined to mil- spec M16/M4 specifications and features M4 feedramps.
Your choice of 3 different muzzle devices (choose type with dropdown menu)
Optional Upgrades (use the dropdown menu to select):
(Only $94 – save $6 vs regular price)
AT3 Tactical partnered with the best BCG manufacturer in the industry – Toolcraft Inc – to produce these Top-Tier Bolt Carrier Groups. They feature M16-style carriers, MPI/HPT inspected bolts, and properly staked grade 8 gas key screws.
Your choice of Standard GI or Extended-Latch Charging Handle
(Discounted Pricing – Save $4 vs regular price)
Quality 7075-T6 charging handles – choose between standard latch and extended latch designs.
This product is built-to-order in our Minnesota facility. Quality takes time – please allow up to 7 days for your order to ship.
All AT3 upper assemblies come with a Lifetime Warranty – if you ever have an issue, let us know, and we’ll make it right. It’s that simple.
Don’t see the options you’re looking for? Let us quote you a custom upper – contact us now.
- Barrel Length: 16″
- Total Assembly Length: 24.5″
- Gas System: Carbine
- Barrel Profile: M4 profile
- Twist Rate: 1:7
- Barrel Steel: 4150 Chrome Moly Vanadium
- Barrel Finish: QPQ Corrosion Resistant (Nitride)
- Chamber: 5.56 NATO
- Muzzle Thread: 1/2-28
- Barrel Extension: M4
- Diameter at Gas Block: .750″
- Gas Block Type: Low-profile
- Receiver Material: Forged 7075 T6
3 reasons why AT3 Complete Uppers are better than the rest.
1 – Quality Where it Counts
The single most important component of an accurate AR-15 is the barrel. AT3 uppers are built using Ballistic Advantage barrels with a Sub-MOA Accuracy Guarantee.
But the quality doesn’t stop at the barrel. From the industry-leading Aero Upper to the precision machined AT3 handguard and muzzle device, this upper assembly offers quality without compromises.
Many of the “bargain” complete uppers on the market source their parts from the lowest bidder – at the expense of accuracy and reliable function. AT3 is committed to using only top-quality components in our upper assemblies.
2 – Guaranteed Reliability
AT3 complete uppers are assembled with strict quality controls, test-fired before shipment, and carefully packaged for delivery to the customer. All AT3 complete uppers offer a Lifetime Warranty – if you ever have an issue, let us know, and we’ll make it right. It’s that simple.
3 – Unbeatable Value
When you buy a complete upper, you’ll save up to 20% off vs purchasing the components separately. Our complete uppers are not the cheapest on the market, but they deliver unbeatable quality in the price range. We sell direct to the customer, and cut out the middle-men, to deliver the best value in AR-15 upper assemblies.
Have Questions About this Product?
Purchased the complete upper, product arrived fast and free shipping.
Fit and finish is excellent, paired up with both Spikes and Stag lowers.
Thank you William for spending some time on the phone going over some additional parts.
Thank you Zac for going over the upgraded barrel options.
Will be ordering from them again on future builds.
Thank you guys !
Working on my first build.
Fit, finish and quality seem top notch.
I've not finished the lower yet, but I will update after testing.
3 calls to Zac was like talking to an old friend.
Fast shipping and outstanding service.
Will be buying from these folks again.