Rifle · SAAMI
.270 Weatherby Magnum
The hypervelocity .270 — driving bullets at speeds Jack O'Connor's beloved .270 Winchester couldn't approach.
- Caliber
- 0.2773″ · 7.043 mm
- Introduced
- 1943
- Case
- Belted
- Parent
- .300 H&H Magnum
- Primary use
- Hunting, Long Range
- Status
- Active
- Introduced
- 1943
- Type
- Rifle
- Origin
- United States
- Inventor
- Roy Weatherby
- Manufacturer
- Weatherby
- Standard
- SAAMI
- Status
- Active
- Availability
- Common
- Case capacity
- 91 gr H₂O
- Twist (typical)
- 1:10
- Primer
- Large Rifle Magnum
- Case type
- Belted
- Max pressure
- 65,000 psi
- Eff. range
- 500 yd
- Max range
- 1500 yd
- Recoil
- 20–28 ft·lb
Introduced by Weatherby
Ballistics
Published velocity/energy data isn't available for .270 Weatherby Magnum. Parent case: .375 H&H Magnum.
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 ⌀ | 7.04 | 0.277 | ✓ |
| Neck ⌀ | 7.75 | 0.305 | ✓ |
| Shoulder ⌀ | 12.50 | 0.492 | ✓ |
| Shoulder angle | — | — | |
| Base ⌀ | 13.00 | 0.512 | ✓ |
| Rim ⌀ | 13.50 | 0.531 | ✓ |
| Belt ⌀ | 13.51 | 0.532 | ✓ |
| Rim thickness | 1.30 | 0.051 | ✓ |
| Neck length | 8.33 | 0.328 | ≈ |
| Case length | 64.74 | 2.549 | ✓ |
| Overall length | 83.69 | 3.295 | ✓ |
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. .270 Weatherby Magnum is highlighted below.
Missing a dimension for .270 Weatherby Magnum? Some case measurements aren't in a published SAAMI/CIP drawing yet. Have a factory or reamer print? Send it → — verified hard-to-find data earns a free Lindcott sticker.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
Suitable powders
8 reloading powders listed for .270 Weatherby Magnum, 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.
Firearms chambered in .270 Weatherby Magnum
12 models in the database chamber .270 Weatherby Magnum. Browse all →
Lineage
Direct parent is .300 H&H (shortened, blown-out, necked to .277); .375 H&H is the grandparent since .300 H&H itself derives from it.
Connected reference
History
One of Weatherby's original cartridges. The great gun writer Jack O'Connor championed the standard .270 Winchester; Weatherby's magnum version outperformed it by 400-500 fps. Their philosophical battle — O'Connor favoring light loads, Weatherby favoring maximum velocity — defined American hunting cartridge debate for 30 years.
FAQs
- What twist rate does .270 Weatherby Magnum use?
- .270 Weatherby Magnum typically uses a 1:10 twist rate.
- What bullet diameter is .270 Weatherby Magnum?
- .270 Weatherby Magnum uses a 0.2773″ (7.043 mm) diameter bullet.
- Is .270 Weatherby Magnum still in production?
- .270 Weatherby Magnum is active; typical availability is common.
- What is .270 Weatherby Magnum used for?
- .270 Weatherby Magnum is primarily used for hunting, long range.
- What is .270 Weatherby Magnum based on?
- .270 Weatherby Magnum is derived from the .375 H&H Magnum case.
- What are the best powders for .270 Weatherby Magnum?
- Reloading powders commonly listed for .270 Weatherby Magnum include N550, Norma 204, N560, Norma MRP, among 8 suitable options.
Sources & provenance
- Standard SAAMI — SAAMI cartridge & chamber drawing — .270 Weatherby Magnum
- Standard SAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawings archived
- Standard SAAMI (Sporting Arms and Ammunition Manufacturers' Institute) — ANSI/SAAMI Z299.4 – 2015 (Centerfire Rifle) — Velocity & Pressure / Cartridge & Chamber Drawings · grain_ballistics, representative_gun archived
- Manufacturer Weatherby — Weatherby Ballistics Chart · grain_ballistics, representative_gun
- Manufacturer Nosler — 270 Caliber 140gr AccuBond (50ct) — component bullet spec page · grain_ballistics, representative_gun archived
- Manufacturer Nosler — 270 Wby Mag 150gr AccuBond Long Range Trophy Grade Ammunition · grain_ballistics, representative_gun archived
- Secondary .270 Weatherby Magnum — Wikipedia (pointer to cited Weatherby/H&H sourcing) · parent_cartridge
- Secondary Head to Head / Behind the Bullet Weatherby coverage — American Hunter (NRA) · parent_cartridge
- Secondary .270 Wby. Mag.: The Original Weatherby — American Rifleman (NRA) · parent_cartridge
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 22 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →