Rifle · CIP
.666T
.666T is a rimless bottlenecked rifle cartridge of Turkey origin.
- Caliber
- 0.2646″ · 6.72 mm
- Introduced
- 2022
- Case
- Rimless
- Parent
- .308 Winchester
- Primary use
- Hunting
- Status
- Active
- Introduced
- 2022
- Type
- Rifle
- Origin
- Turkey
- Inventor
- MKE (approx: maker of record)
- Manufacturer
- MKE
- Standard
- CIP
- Status
- Active
- Availability
- Limited
- Case capacity
- 57 gr H₂O
- Twist (typical)
- 1:8
- Primer
- Large Rifle
- Case type
- Rimless
- Max pressure
- 63,092 psi, CIP transducer
- Eff. range
- 400 yd
- Max range
- 2000 yd
- Recoil
- 11.8–13.3 ft·lb
Introduced by MKE
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for .666T, so this is the shape gravity alone gives the advertised velocity. Drag would steepen it. The tool below solves real loads through their published G1 or G7 model.
Open in Ballistic Compare- Parent case
- .308 Winchester
Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).
Dimensionscase measurements · scale drawing · size vs familiar rounds
Case dimensions — the scale drawing at the top of the page is built from these.
CIP TDCC · verified| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 6.72 | 0.265 | ✓ |
| Neck ⌀ | 7.49 | 0.295 | ✓ |
| Shoulder ⌀ | 11.73 | 0.462 | ✓ |
| Shoulder angle | 40° | — | ≈ |
| Base ⌀ | 11.96 | 0.471 | ✓ |
| Rim ⌀ | 12.01 | 0.473 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.37 | 0.054 | ✓ |
| Neck length | 7.92 | 0.312 | ≈ |
| Case length | 52.00 | 2.047 | ✓ |
| Overall length | 75.00 | 2.953 | ✓ |
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. .666T is highlighted below.
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 around 2022.
FAQs
- What twist rate does .666T use?
- .666T typically uses a 1:8 twist rate.
- What bullet diameter is .666T?
- .666T uses a 0.2646″ (6.72 mm) diameter bullet.
- Is .666T still in production?
- .666T is active; typical availability is limited.
- What is .666T used for?
- .666T is primarily used for hunting.
- What is .666T based on?
- .666T is derived from the .308 Winchester case.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
