Lindcott Armory Rifle · SAAMI
.340 Weatherby Magnum
The most powerful .338 in a standard-length action for decades.
- Caliber
- 0.338″ · 8.585 mm
- Introduced
- 1962
- Case
- Belted
- Parent
- .375 H&H Magnum
- Primary use
- Big Game, Dangerous Game, Hunting
- Status
- Active
- Introduced
- 1962
- Type
- Rifle
- Origin
- United States
- Inventor
- Roy Weatherby
- Manufacturer
- Weatherby
- Standard
- SAAMI
- Status
- Active
- Availability
- Common
- Case capacity
- 99 gr H₂O
- Twist (typical)
- 1:10
- Primer
- Large Rifle Magnum
- Case type
- Belted
- Max pressure
- 63,800 psi
- Eff. range
- 500 yd
- Max range
- 1500 yd
- Recoil
- 30–42 ft·lb
Ballistics
Real trajectory computed from a representative load — HSM Trophy Gold 250 gr, 2,760 fps, BC 0.356 G7 · 100 yd zero.
| Range | Velocity | Energy | Drop (in) | Drop (MOA) |
|---|---|---|---|---|
| 0 yd | 2759 | 4226 | -1.5″ | — |
| 100 yd | 2633 | 3848 | 0.0″ | 0.0 |
| 200 yd | 2509 | 3493 | -3.5″ | -1.7 |
| 300 yd | 2388 | 3165 | -12.6″ | -4.0 |
| 400 yd | 2271 | 2862 | -27.7″ | -6.6 |
| 500 yd | 2157 | 2581 | -49.6″ | -9.5 |
| 600 yd | 2045 | 2321 | -79.0″ | -12.6 |
| 700 yd | 1936 | 2081 | -116.8″ | -15.9 |
| 800 yd | 1831 | 1860 | -163.6″ | -19.5 |
Point-mass G7/G1 drag model, standard atmosphere — within ~2% of reference solvers to 1000 yd; real barrels and conditions vary. Open in Ballistic Compare →
Performance
Buy links open .340 Weatherby Magnum ammunition at Rivertown Munitions.
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 ⌀ | 12.57 | 0.495 | ✓ |
| Shoulder angle | — | — | |
| Base ⌀ | 13.00 | 0.512 | ✓ |
| Rim ⌀ | 13.50 | 0.531 | ✓ |
| Belt ⌀ | 13.50 | 0.531 | ✓ |
| Rim thickness | 1.24 | 0.049 | ✓ |
| Neck length | 8.64 | 0.340 | ≈ |
| Case length | 71.76 | 2.825 | ✓ |
| Overall length | 93.98 | 3.700 | ~ |
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. .340 Weatherby Magnum is highlighted below.
Missing a dimension for .340 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
In production — 22 active loads across 14 brands. Top 15 shown · see all 22 →.
| Brand | Load | Grain | Bullet | FPS | ft·lb | BC |
|---|---|---|---|---|---|---|
| Hornady | Precision Hunter | 225 | ELD-X | 3,000 | 4,496 | 0.315 G7 |
| Barnes | VOR-TX TTSX BT | 225 | TTSX BT | 2,960 | 4,377 | 0.215 G7 |
| Barnes | VOR-TX | 225 | TTSX BT | 2,941 | 4,321 | 0.215 G7 |
| Weatherby | Select Plus | 225 | Nosler Partition | 2,941 | 4,321 | 0.550 G1 |
| Weatherby | Select Barnes TTSX | 225 | TTSX BT | 2,941 | 4,321 | 0.215 G7 |
| Weatherby | Select Plus Nosler AccuBond | 225 | Nosler AccuBond | 2,941 | 4,321 | 0.278 G7 |
| Nosler | Trophy Grade AccuBond | 250 | AccuBond | 2,941 | 4,801 | 0.318 G7 |
| Hornady | Precision Hunter ELD-X | 225 | ELD-X | 2,900 | 4,201 | 0.315 G7 |
| Weatherby | Select Plus | 250 | Nosler AccuBond | 2,849 | 4,505 | 0.318 G7 |
| Weatherby | Select Plus | 250 | AccuBond CT | 2,760 | 4,228 | 0.318 G7 |
| HSM | Trophy Gold | 250 | Berger Hybrid | 2,760 | 4,228 | 0.356 G7 |
| Berger | Hunting | 300 | Elite Hunter OTM | 2,600 | 4,502 | 0.417 G7 |
| Swift | A-Frame | 225 | A-Frame SP | 3,100 | 4,800 | — |
| RWS | HIT | 225 | HIT | 3,100 | 4,800 | — |
| Winchester | Nosler AccuBond | 225 | AccuBond | 3,100 | 4,800 | — |
Velocities are manufacturer-stated (test-barrel). Discontinued loads dimmed.
Suitable powders
3 reloading powders listed for .340 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 .340 Weatherby Magnum
12 models in the database chamber .340 Weatherby Magnum. Browse all →
Lineage
Connected reference
History
Introduced in 1962 for hunters who wanted more than .338 Win Mag but didn't need the extreme dimensions of African express cartridges. Found success with Alaskan guides and hunters pursuing large bears and moose at extended ranges.
FAQs
- What twist rate does .340 Weatherby Magnum use?
- .340 Weatherby Magnum typically uses a 1:10 twist rate.
- What bullet diameter is .340 Weatherby Magnum?
- .340 Weatherby Magnum uses a 0.338″ (8.585 mm) diameter bullet.
- Is .340 Weatherby Magnum still in production?
- .340 Weatherby Magnum is active; typical availability is common.
- What is .340 Weatherby Magnum used for?
- .340 Weatherby Magnum is primarily used for big game, dangerous game, hunting.
- What is .340 Weatherby Magnum based on?
- .340 Weatherby Magnum is derived from the .375 H&H Magnum case.
- What are the best powders for .340 Weatherby Magnum?
- Reloading powders commonly listed for .340 Weatherby Magnum include N170, Reloader 25, Reloader 26.
Sources & provenance
- StandardSAAMI — SAAMI cartridge & chamber drawing — .340 Weatherby Magnum
- StandardSAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawingsarchived
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 →