Skip to content
Lindcott Armory

Rifle · SAAMI

6mm ARC

Also known as 6mm Advanced Rifle Cartridge

Modern long-range AR-15 cartridge.

Caliber
0.2433″ · 6.18 mm
Introduced
2020
Case
Rebated
Parent
6.5 Grendel
Primary use
Competition, Hunting, Target
Status
Active

Buy this cartridge

Buy at Rivertown

Buying from Rivertown

Partner link
VelocityBeing verified
EnergyBeing verified
Typical grains90 · 105 · 108 gr
Identity
Introduced
2020
Type
Rifle
Origin
United States
Inventor
Hornady
Manufacturer
Hornady
Standard
SAAMI
Status
Active
Availability
Common
Build
Case capacity
34.5 gr H₂O
Twist (typical)
1:7.5
Primer
Small Rifle
Case type
Rebated
Pressure & range
Max pressure
52,000 psi
Eff. range
1000 yd
Recoil
6–9 ft·lb

Introduced by Hornady

Ballistics

Published velocity/energy data isn't available for 6mm ARC. Parent case: 6.5 Grendel.

Performance

Best for Withheld until verified
Best for Withheld until verified
Dimensionscase measurements · scale drawing · size vs familiar rounds

Case dimensions — the scale drawing at the top of the page is built from these.

SAAMI · verified
Measuremmin✓
Bullet ⌀ 6.180.243 ✓
Neck ⌀ 6.960.274 ✓
Shoulder ⌀ 10.920.430 ✓
Shoulder angle 30°— ✓
Base ⌀ 11.200.441 ✓
Rim ⌀ 11.200.441 ✓
Belt ⌀ n/a
Rim thickness 1.500.059 ✓
Neck length 5.950.234 ≈
Case length 37.851.490 ✓
Overall length 57.402.260 ✓

Size vs familiar rounds

Drawn at true 1:1 — every case is accurate relative to the others. Absolute size depends on your screen's pixel density, so measuring one against a real ruler may be off. 6mm ARC is highlighted below.

Factory loads

Verification

Being verified

Advertised FPS, energy, and BC are withheld until loads clear verification.

Suitable powders

10 reloading powders listed for 6mm ARC, fastest to slowest. Cross-reference in the finder →

N120N130Vihtavuori N133H3352015N135N550Vihtavuori N140N540Vihtavuori N150
Reloading costestimate cost per round vs factory

Estimate your cost per round and how it compares to factory. Inputs are yours — nothing is stored.

Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.

Firearms chambered in 6mm ARC

12 models in the database chamber 6mm ARC. Browse all →

Christensen Arms CA-10 6mm ARC 20-inchChristensen Arms MPR 6mm ARC 20-inchCMMG Resolve Mk4 6mm ARC 16-inchCMMG Dissent Mk4 6mm ARC 16-inchAero Precision M4E1 6mm ARC 20-inchHowa Mini Action 300 BlackoutHowa Mini Action 224 ValkyrieChristensen Arms CA-15 G2 6mm ARC 16-inchSavage Arms Axis II 6mm ARC 22-inchRuger Precision Rifle 6mm ARC 26-inchSavage Arms MSR 10 Hunter 6mm ARC 20-inchSavage Arms MSR 15 6mm ARC 18-inch

Lineage

Immediate parent
6.5 Grendel
Direct descendants (2)
.338 ARC
Family TreeOpen 6mm ARC in the interactive cartridge family tree

Connected reference

Loads82 factory loads for 6mm ARCReloading10 suitable powders — cross-referenceFirearmsFirearms in 6mm ARC

History

Introduced by Hornady in 2020, developed with military input for long-range precision in AR-15 platforms. Based on the 6.5 Grendel case necked to 6mm, providing greater case capacity than the 6.8 SPC-derived .224 Valkyrie despite a similar mission. Rapidly adopted by precision rifle competitors and special operations forces.

FAQs

What twist rate does 6mm ARC use?
6mm ARC typically uses a 1:7.5 twist rate.
What bullet diameter is 6mm ARC?
6mm ARC uses a 0.2433″ (6.18 mm) diameter bullet.
Is 6mm ARC still in production?
6mm ARC is active; typical availability is common.
What is 6mm ARC used for?
6mm ARC is primarily used for competition, hunting, target.
What is 6mm ARC based on?
6mm ARC is derived from the 6.5 Grendel case.
What are the best powders for 6mm ARC?
Reloading powders commonly listed for 6mm ARC include N120, N130, Vihtavuori N133, H335, among 10 suitable options.

Sources & provenance

Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 82 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →