From: $699.00
Most AR-15 complete uppers come with parts you’re just going to swap out as soon as you open the box. At Grendel Hunter, we don’t believe in making you pay for parts you’re just going to throw in a spare parts bin. Have it built your way from the beginning and skip the box of leftover parts.
Our Custom Upper Builder lets you spec out your upper exactly how you want it from the start. We offer numerous options for barrels, handguards, BCG’s etc. The base price is for a complete, fully assembled upper. If you want to upgrade a component—like switching a mil-spec charging handle for an ambidextrous one—just select your preference and the total at the bottom of the page will update automatically.
The base price includes a Bolt Carrier Group. However, if you already have a BCG for this caliber, we aren’t going to force you to buy another one. Selecting “None” for that component will give you a $100 discount at checkout.
(Please Note: This $100 discount is applied in the cart and will not be reflected in the “Grand Total” at the bottom of this builder page.)
At the bottom of this page we’ve included in-depth descriptions of various components as well videos and FAQ’s.
All of the data below was gathered by Grendel Hunter staff shooting the various loads in 10+ round strings through a chronograph. The data was then entered into a ballistics calculator to provide us with velocities, energy and trajectories at various ranges. For our calculations we used the following conditions:
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 3178 | 1570 | -2.7 |
| 100 | 2846 | 1259 | 0.0 |
| 200 | 2539 | 1001 | -1.7 |
| 300 | 2252 | 788 | -8.7 |
| 400 | 1984 | 612 | -22.7 |
| 500 | 1737 | 469 | -45.5 |
| 600 | 1514 | 356 | -79.9 |
| 700 | 1323 | 272 | -129.5 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 3001 | 1500 | -2.7 |
| 100 | 2711 | 1224 | 0.0 |
| 200 | 2440 | 991 | -2.1 |
| 300 | 2185 | 795 | -10.0 |
| 400 | 1946 | 630 | -25.3 |
| 500 | 1724 | 495 | -49.7 |
| 600 | 1523 | 386 | -85.9 |
| 700 | 1346 | 302 | -137.1 |
| 800 | 1201 | 240 | -207.6 |
| 900 | 1091 | 198 | -302.0 |
| 1000 | 1013 | 171 | -425.4 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2964 | 1560 | -2.7 |
| 100 | 2731 | 1325 | 0.0 |
| 200 | 2511 | 1120 | -2.0 |
| 300 | 2301 | 940 | -9.5 |
| 400 | 2101 | 784 | -23.7 |
| 500 | 1912 | 649 | -45.7 |
| 600 | 1734 | 534 | -77.2 |
| 700 | 1569 | 437 | -120.3 |
| 800 | 1420 | 358 | -177.5 |
| 900 | 1289 | 295 | -251.9 |
| 1000 | 1179 | 247 | -347.3 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2698 | 1665 | -2.7 |
| 100 | 2522 | 1454 | 0.0 |
| 200 | 2352 | 1265 | -2.8 |
| 300 | 2190 | 1096 | -11.9 |
| 400 | 2033 | 945 | -28.3 |
| 500 | 1884 | 812 | -53.0 |
| 600 | 1742 | 694 | -87.6 |
| 700 | 1609 | 592 | -133.6 |
| 800 | 1484 | 504 | -193.0 |
| 900 | 1371 | 430 | -268.3 |
| 1000 | 1271 | 369 | -361.9 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 3331 | 1429 | -2.7 |
| 100 | 2923 | 1100 | 0.0 |
| 200 | 2552 | 838 | -1.4 |
| 300 | 2210 | 629 | -8.2 |
| 400 | 1895 | 462 | -22.2 |
| 500 | 1612 | 335 | -45.9 |
| 600 | 1369 | 241 | -83.1 |
| 700 | 1178 | 179 | -138.8 |
| 800 | 1048 | 142 | -219.4 |
| 900 | 963 | 119 | -331.1 |
| 1000 | 899 | 104 | -479.7 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 3246 | 1520 | -2.7 |
| 100 | 2939 | 1247 | 0.0 |
| 200 | 2654 | 1016 | -1.4 |
| 300 | 2386 | 822 | -7.7 |
| 400 | 2134 | 657 | -20.2 |
| 500 | 1898 | 520 | -40.2 |
| 600 | 1681 | 408 | -70.0 |
| 700 | 1484 | 318 | -112.1 |
| 800 | 1313 | 249 | -170.0 |
| 900 | 1175 | 199 | -248.1 |
| 1000 | 1072 | 166 | -351.1 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 3089 | 1483 | -2.7 |
| 100 | 2764 | 1187 | 0.0 |
| 200 | 2462 | 942 | -1.9 |
| 300 | 2180 | 739 | -9.6 |
| 400 | 1917 | 571 | -24.6 |
| 500 | 1676 | 437 | -49.1 |
| 600 | 1461 | 332 | -86.0 |
| 700 | 1279 | 254 | -139.3 |
| 800 | 1137 | 201 | -213.8 |
| 900 | 1038 | 167 | -315.0 |
| 1000 | 967 | 145 | -448.1 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2916 | 1416 | -2.7 |
| 100 | 2632 | 1154 | 0.0 |
| 200 | 2366 | 932 | -2.4 |
| 300 | 2115 | 745 | -11.0 |
| 400 | 1881 | 589 | -27.4 |
| 500 | 1664 | 461 | -53.7 |
| 600 | 1469 | 359 | -92.5 |
| 700 | 1301 | 282 | -147.5 |
| 800 | 1166 | 226 | -223.0 |
| 900 | 1066 | 189 | -324.0 |
| 1000 | 994 | 165 | -455.3 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2821 | 1502 | -2.7 |
| 100 | 2551 | 1228 | 0.0 |
| 200 | 2297 | 996 | -2.7 |
| 300 | 2058 | 799 | -12.0 |
| 400 | 1834 | 635 | -29.6 |
| 500 | 1627 | 500 | -57.5 |
| 600 | 1442 | 393 | -98.6 |
| 700 | 1283 | 311 | -156.4 |
| 800 | 1155 | 252 | -235.3 |
| 900 | 1061 | 212 | -340.1 |
| 1000 | 992 | 186 | -475.6 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2689 | 1445 | -2.7 |
| 100 | 2470 | 1219 | 0.0 |
| 200 | 2261 | 1022 | -3.1 |
| 300 | 2063 | 851 | -12.9 |
| 400 | 1876 | 703 | -31.0 |
| 500 | 1700 | 577 | -58.9 |
| 600 | 1538 | 472 | -98.9 |
| 700 | 1392 | 387 | -153.6 |
| 800 | 1264 | 319 | -226.2 |
| 900 | 1159 | 268 | -320.6 |
| 1000 | 1078 | 232 | -440.7 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
| Range (Yds) | Velocity (FPS) | Energy (Ft-Lbs) | Drop (Inches) |
|---|---|---|---|
| 0 (Muzzle) | 2588 | 1532 | -2.7 |
| 100 | 2416 | 1335 | 0.0 |
| 200 | 2251 | 1158 | -3.3 |
| 300 | 2092 | 1001 | -13.5 |
| 400 | 1940 | 861 | -31.6 |
| 500 | 1795 | 737 | -59.0 |
| 600 | 1658 | 629 | -97.1 |
| 700 | 1531 | 536 | -147.9 |
| 800 | 1413 | 457 | -213.5 |
| 900 | 1307 | 391 | -296.5 |
| 1000 | 1215 | 338 | -399.8 |
Note: Data calculated with a 100-yard zero, 2.65″ scope height, and environmental parameters of 59°F, 50% humidity, and 1,000 FT altitude.
Looking for maximum terminal performance out of your 6mm ARC? In this post, we put Druid Hill Armory’s 65gr and 85gr Maker T-REX custom ammunition to the test using an 18″ Grendel Hunter upper and 10% ballistic gel. Discover how these CNC-machined, solid-copper monolithic monsters compare to traditional lead-core rounds in penetration, weight retention, and immediate expansion.
See how the Hornady 103gr ELD-X performs in the 6mm ARC at 100 and 370 yards. Detailed ballistic gel results, velocities, and expansion data for AR-15 hunters
Your barrel is the heart of the system. We offer 16″, 18″, 20″, and 22″ lengths in a Medium Contour so you can find the perfect balance between velocity and portability for your application.
Material: 416R Stainless Steel for accuracy and durability.
Finishes: Choose between Uncoated Stainless, Black Cerakote, or a Bead Blasted Stainless finish.
Fluting: All Lengths available in a Non-Fluted, classic profile or with Straight Flutes for weight savings.
Forget standard, mass-produced mil-spec forgings. We designed our Grendel Hunter Billet uppers to move beyond the “basic” look of a standard AR. Billet allows us the design freedom to create sharper lines and a more modern aesthetic that you just can’t get from a forging.
We didn’t just design an upper; we designed a system. Our uppers and handguards are engineered to match up in an almost monolithic way, creating a seamless, integrated look.
Slick Side: For the minimalist—no forward assist, shell deflector, or dust cover.
Traditional: Includes all standard features for those who want a classic style upper.
Premium Finishing: Available in Black Hardcoat Anodized, Magpul FDE Cerakote, and Magpul OD Green Cerakote. Note: All Cerakoted uppers are anodized on the interior for maximum durability and smooth cycling.
Every Grendel Hunter handguard is designed to integrate seamlessly with our billet uppers, creating a near-monolithic look and a rock-solid mounting platform. While they share the same rugged DNA, each version has a unique style.
Material: Lightweight, high-strength 6061-T6 Aluminum.
Rock-Solid Lockup: A heavy-duty Steel Barrel Nut and Steel Retention System ensure your rail doesn’t shift, even with heavy use.
Anti-Rotation Tabs: Integrated tabs prevent the rail from twisting under torque.
Slim Profile: A 1.3″ inside diameter provides a modern, ergonomic “C-clamp” grip and a sleek look.
V1:
Front Profile: Aggressive Slant-Cut
Top Rail: Competition Style (Rails at front and back only)
M-LOK Slots: Sides and Bottom
Weight: Our Lightest Option
The V1 is our lightest handguard. By utilizing a competition-style top rail and a sleek slant-cut front, we’ve shed every unnecessary ounce without sacrificing mounting space.
V2:
Front Profile: Traditional Squared-Off
Top Rail: Competition Style (Rails at front and back only)
M-LOK Slots: Sides and Bottom
Weight: Balanced
If you prefer a more traditional look, the V2 features a squared-off front end. It maintains the competition-style top rail for weight savings.
V3:
Front Profile: Aggressive Slant-Cut
Top Rail: Full Picatinny (Continuous top rail)
M-LOK Slots: Full 360° (All sides)
Weight: Built for utility, but our heaviest option
The V3 is our most capable rail. It features a full-length Picatinny top rail and M-LOK slots surrounding the entire circumference. This is the go-to choice for hunters running thermal clip-ons, IR illuminators, or side-mounted accessories.
Headspace Check: We perform a manual headspace check for every upper using the specific barrel and bolt you’ve selected.
Optimized Extractor Tension: Excessive tension is a leading cause of malfunctions and extractor failure. We are meticulous about our extractor tension being at the “sweet spot”—ensuring reliable cycling without putting unnecessary stress on the steel.
Radiused Extractor Geometry: We avoid the “sharp fangs” found on most extractors. By having smooth corners on the extractor claw, we prevent the steel from digging into the brass case rim, ensuring the ejector can “kick” the brass out at the exact right microsecond for a clean ejection cycle.
Built to Last: Our bolts are machined from 9310 Steel, shot-peened for fatigue resistance, and Magnetic Particle Inspected (MPI).
We offer four distinct finishes, each offering a significant upgrade over the old Mil-Spec phosphate in terms of lubricity, hardness, and ease of cleaning.
Black Nitride
Surface Hardness: ~740 HV (Vickers)
The Process: A salt-bath thermo-chemical treatment that hardens the steel.
The Benefit: Far more durable and smoother than original Mil-Spec magnesium phosphate with excellent corrosion resistance.
Nickel Boron (NiB)
Surface Hardness: ~1800 HV (Vickers)
The Process: UCT EXO® (High Boron content).
The Benefit: An extremely hard, durable finish with a very low friction coefficient. It’s smooth and wipes clean easily.
DLC (Diamond-Like Carbon)
Surface Hardness: ~2300 HV (Vickers)
The Process: Next-level Plasma Enhanced Chemical Vapor Deposition (PECVD)
The Benefit: High hardness, Excellent abrasive wear resistance, Low thermal conductivity, Ultra-Low friction level.
P51+ High Polish Black
Carrier: M16 Auto Profile (8620 Steel) for smooth cycling and increased mass.
Gas Key: 4130 Steel with properly staked Grade 8 fasteners.
Bolt: 6.5 Grendel / 6mm ARC / .22 ARC
Small Parts: 4140 Steel Cam Pin and Hard Chrome Firing Pin.
We exclusively use adjustable blocks in our uppers. With the explosion in popularity that suppressors have enjoyed in recent years, it just makes sense to have the ability to tune the gas. There are two models to choose from.
Note: Every upper is test-fired and shipped pre-set for reliable unsuppressed firing.
Best For: Those who don’t plan to suppress or shooters who will suppress and want to tune their gas once and leave it. Generally requires handguard removal for adjustment since cutouts in handguards don’t always align with the adjustment screw. Handguard removal is as simple as removing two hex bolts, but it is an extra step.
Design: Side-access adjustment (1/16” Hex) with a front-facing locking screw.
Material: 4140 Steel with a Black Nitride finish.
Best For: Those who suppress or who like to really fine tune their rifles.
Design: Ball-detent system with 22 audible clicks of adjustment across the gas port and zero-shutoff.
Ease of Use: Front-access adjustment screw (1/8″ Hex) allows for tuning without removing the handguard.
Performance: Eliminates the “violent” over-gassed cycle common with suppressors, reducing carrier speed and heat.
Materials: 4140 PHT or 303 Stainless Steel.
Finishes: Black Nitride, Stainless, or Bead Blasted Stainless.
It depends on how you define “optimal.” In theory, if it takes 24″–26″ to get 100% of the powder burn inside the bore, then anything less is technically a compromise. But for most of us, carrying a “musket” in the field isn’t exactly optimal, either.
Ultimately, the right length comes down to your specific requirements. For example:
If you’re running a suppressor, getting in and out of a side-by-side, or trekking long distances, the portability of an 18″ barrel is hard to beat.
If you’re calling coyotes a couple hundred yards from the truck and shooting off a tripod, you might prioritize the higher velocity and flatter trajectory of a 22″ barrel over weight savings.
Choose the length that fits how you actually hunt, not the one that strangers on the internet tell you is “optimal.”
Yes. You choose the components above and we assemble and test fire with those parts.
Yes. For every upper we build, we take the specific barrel and bolt the customer has selected and perform a headspace check prior to assembly.
Velocity differences between different length barrels can vary somewhat depending on the load and how quickly a specific powder burns. In our testing, we generally see ~ 30 fps of velocity gained per inch of barrel length between 16″ and 22″ with the 6mm ARC.
We ship the same or next business day. Since our website has a live inventory and we only sell things that actually exist on our shelves, we do not have lead times.
Unfortunately, we do not accept backorders. It’s Grendel Hunter’s policy to only take a customer’s money for things that exist.
If a specific component is out of stock, you can go to that item’s individual product page and join the “Back in Stock” email notification list.
When it comes to choosing a handguard’s length, a lot of it is personal preference. Here are a few things to consdier though:
Click here to browse our other Uppers. Don’t forget magazines!
Hunter (verified owner) –
Great upper. Came extremely quick, impressed with how it shoots.