Rifle · SAAMI
8.6 Blackout
A suppressor-optimized bolt-action cartridge that dominates subsonic performance.
- Caliber
- 0.338″ · 8.585 mm
- Introduced
- 2022
- Case
- Rimless
- Parent
- 6.5 Creedmoor
- Primary use
- Hunting, Self-Defense, Long Range
- Status
- Active
- Introduced
- 2022
- Type
- Rifle
- Origin
- United States
- Inventor
- Q LLC / Kevin Brittingham
- Manufacturer
- Q LLC / Hornady
- Standard
- SAAMI
- Status
- Active
- Availability
- Common
- Case capacity
- 50 gr H₂O
- Twist (typical)
- 1:6
- Primer
- Large Rifle
- Case type
- Rimless
- Max pressure
- 62,000 psi, SAAMI transducer
- Eff. range
- 300 yd
- Max range
- 5550 yd
- Recoil
- 8–12 ft·lb
- Subsonic
- Capable
Ballistics
Published velocity/energy data isn't available for 8.6 Blackout. Parent case: 6.5 Creedmoor.
Performance
Dimensionscase measurements · scale drawing · size vs familiar rounds
Case dimensions — the scale drawing at the top of the page is built from these.
SAAMI · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 8.59 | 0.338 | ✓ |
| Neck ⌀ | 9.30 | 0.366 | ~ |
| Shoulder ⌀ | 11.77 | 0.464 | ~ |
| Shoulder angle | 30° | — | ✓ |
| Base ⌀ | 11.95 | 0.470 | ✓ |
| Rim ⌀ | 11.99 | 0.472 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.37 | 0.054 | ✓ |
| Neck length | 8.39 | 0.330 | ≈ |
| Case length | 42.80 | 1.685 | ✓ |
| Overall length | 71.37 | 2.810 | ~ |
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. 8.6 Blackout is highlighted below.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
Suitable powders
2 reloading powders listed for 8.6 Blackout, fastest to slowest. Cross-reference in the finder →
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.
Lineage
Connected reference
History
Introduced by Q LLC (founded by Kevin Brittingham, also founder of SilencerCo) in 2022. Designed around suppressed bolt-action rifles for hunting, inspired by the 9x39mm Russian subsonic sniper concept. The Q Fix uses it. SAAMI accepted it for standardization in January 2026.
FAQs
- What twist rate does 8.6 Blackout use?
- 8.6 Blackout typically uses a 1:6 twist rate.
- What bullet diameter is 8.6 Blackout?
- 8.6 Blackout uses a 0.338″ (8.585 mm) diameter bullet.
- Is 8.6 Blackout still in production?
- 8.6 Blackout is active; typical availability is common.
- What is 8.6 Blackout used for?
- 8.6 Blackout is primarily used for hunting, self-defense, long range.
- What is 8.6 Blackout based on?
- 8.6 Blackout is derived from the 6.5 Creedmoor case.
- What are the best powders for 8.6 Blackout?
- Reloading powders commonly listed for 8.6 Blackout include Lil'Gun, IMR 4227.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 12 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
