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
- 85.7 gr H₂O
- Twist (typical)
- 1:10
- Primer
- Large Rifle Magnum
- Case type
- Belted
- Max pressure
- 62,500 psi, SAAMI transducer
- Eff. range
- 500 yd
- Max range
- 5350 yd
- Recoil
- 20–28 ft·lb
Introduced by Weatherby
Ballistics
Published velocity/energy data isn't available for .270 Weatherby Magnum. Parent case: .300 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 | 8.5° | — | |
| 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
Lineage
Shortened, blown out, necked to .277
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 .300 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 (Sporting Arms and Ammunition Manufacturers' Institute) — ANSI/SAAMI Z299.4 – 2015 (Centerfire Rifle) — Velocity & Pressure / Cartridge & Chamber Drawings · representative_gun, grain_ballistics archived
- Standard SAAMI — SAAMI cartridge & chamber drawing — .270 Weatherby Magnum
- Standard SAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawings archived
- Manufacturer Nosler — 270 Wby Mag 150gr AccuBond Long Range Trophy Grade Ammunition · representative_gun, grain_ballistics archived
- Manufacturer Nosler — 270 Caliber 140gr AccuBond (50ct) — component bullet spec page · grain_ballistics, representative_gun archived
- Manufacturer Weatherby — Weatherby Ballistics Chart · representative_gun, grain_ballistics
- 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
- Secondary .270 Weatherby Magnum — Wikipedia (pointer to cited Weatherby/H&H sourcing) · 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 →
