What twist rate does .300 WSM use?

.300 WSM typically uses a 1:10 twist rate.

What bullet diameter is .300 WSM?

.300 WSM uses a 0.308″ (7.823 mm) diameter bullet.

Is .300 WSM still in production?

.300 WSM is active; typical availability is common.

What is .300 WSM used for?

.300 WSM is primarily used for hunting, long range.

What is .300 WSM based on?

.300 WSM is derived from the .404 Jeffery case.

What are the best powders for .300 WSM?

Reloading powders commonly listed for .300 WSM include N550, N555, Alliant Reloader 16, Vihtavuori N140, among 26 suitable options.

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Rifle · SAAMI

.300 WSM

Also known as .300 Winchester Short Magnum

Near-.300 Win Mag performance from a short-action rifle.

Caliber: 0.308″ · 7.823 mm
Introduced: 2001
Case: Rebated
Parent: .404 Jeffery
Primary use: Hunting, Long Range
Status: Active

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VelocityBeing verified

EnergyBeing verified

Typical grains150 · 165 · 180 gr

Identity

Introduced: 2001
Type: Rifle
Origin: United States
Inventor: Winchester
Manufacturer: Winchester Ammunition
Standard: SAAMI
Status: Active
Availability: Common

Build

Case capacity: 81 gr H₂O
Twist (typical): 1:10
Primer: Large Rifle Magnum
Case type: Rebated

Pressure & range

Max pressure: 65,000 psi, SAAMI transducer
Eff. range: 600 yd
Max range: 5300 yd
Recoil: 20–28 ft·lb

Introduced by Winchester Ammunition

Ballistics

Published velocity/energy data isn't available for .300 WSM. Parent case: .404 Jeffery.

Performance

Best for Withheld until verified

Dimensionscase measurements · scale drawing · size vs familiar rounds

Case dimensions — the scale drawing at the top of the page is built from these.

SAAMI · verified

Measure	mm	in	✓
Bullet ⌀	7.82	0.308	✓
Neck ⌀	8.74	0.344	✓
Shoulder ⌀	13.67	0.538	✓
Shoulder angle	35°	—	✓
Base ⌀	14.12	0.556	✓
Rim ⌀	13.59	0.535	✓
Belt ⌀	n/a
Rim thickness	1.37	0.054	✓
Neck length	7.57	0.298	≈
Case length	53.34	2.100	✓
Overall length	72.64	2.860	✓

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. .300 WSM is highlighted below.

Factory loads

Verification

Being verified

Advertised FPS, energy, and BC are withheld until loads clear verification.

Suitable powders

26 reloading powders listed for .300 WSM, 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.

Powder $/lb Charge (gr) Bullet $/ea Primer $/ea Brass reuses Brass $/ea

Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.

Firearms chambered in .300 WSM

Savage Arms 110 Trail Hunter 6.5 Creedmoor 22-inchTikka T3x Hunter 6.5 PRCWinchester Winchester XPR Suppressor Ready .308 Win 20-inchSavage Arms 110 Engage Hunter XP .300 WSM 24-inchSavage Arms 110 Magnum Hunter .300 WSMSavage Arms Savage 110 Ultralite .308 Win 22-inchMossberg Patriot Synthetic 270 WSMBrowning X-Bolt Max Long Range Hunter 6.5 PRC 24-inchBrowning X-Bolt Pro 300 WSM Carbon Fiber 23-inchBrowning X-Bolt Max Long Range Hunter .300 Win Mag 26-inchWinchester XPR Renegade Long RangeMossberg Patriot .300 WSM 24-inch

Lineage

Family TreeOpen .300 WSM in the interactive cartridge family tree

Connected reference

Reloading26 suitable powders — cross-reference

History

Introduced by Winchester in 2001 as the first WSM. Achieves approximately 95% of .300 Win Mag velocity in a short action. Adopted for some precision rifle applications.

FAQs

What twist rate does .300 WSM use?: .300 WSM typically uses a 1:10 twist rate.
What bullet diameter is .300 WSM?: .300 WSM uses a 0.308″ (7.823 mm) diameter bullet.
Is .300 WSM still in production?: .300 WSM is active; typical availability is common.
What is .300 WSM used for?: .300 WSM is primarily used for hunting, long range.
What is .300 WSM based on?: .300 WSM is derived from the .404 Jeffery case.
What are the best powders for .300 WSM?: Reloading powders commonly listed for .300 WSM include N550, N555, Alliant Reloader 16, Vihtavuori N140, among 26 suitable options.

Sources & provenance

Standard SAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawings archived
Manufacturer Nosler — 300 WSM 180gr AccuBond Trophy Grade Ammunition · representative_gun, grain_ballistics archived
Manufacturer Federal Premium — Power-Shok Rifle 300 WSM Ammo, 180 Grain (300WSMC) · grain_ballistics, representative_gun archived
Manufacturer Remington — Core-Lokt 300 WSM Ammo, 150 Grain · representative_gun, grain_ballistics archived
Manufacturer Federal Premium — Terminal Ascent 300 WSM Ammo, 200 Grain (P300WSMTA1) · representative_gun, grain_ballistics archived
Manufacturer Federal Premium — Fusion Rifle 300 WSM Ammo, 165 Grain (F300WSMFS1) · representative_gun, grain_ballistics archived
Manufacturer Federal Premium — ELD-X 300 WSM Ammo, 200 Grain (P300WSMELDX1) · representative_gun, grain_ballistics archived
Manufacturer Hornady — 300 WSM 200 gr ELD-X Precision Hunter (82208) · grain_ballistics, representative_gun
Manufacturer Federal Premium — Barnes TSX 300 WSM Ammo, 165 Grain (P300WSMG) · grain_ballistics, representative_gun archived

Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 94 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →

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