Pistol · SAAMI
.45 Winchester Magnum
Powerful semi-automatic pistol magnum delivering .44 Magnum-class energy from a gas-operated pistol platform.
- Caliber
- 0.452″ · 11.481 mm
- Introduced
- 1979
- Case
- Rimless
- Parent
- .45 ACP
- Primary use
- Hunting, Self Defense
- Status
- Active
- Introduced
- 1979
- Type
- Pistol
- Origin
- United States
- Inventor
- Winchester / Wildey Moore
- Manufacturer
- Winchester Ammunition
- Standard
- SAAMI
- Status
- Active
- Availability
- Limited
- Case capacity
- 38 gr H₂O
- Twist (typical)
- 1:16
- Primer
- Large Pistol Magnum
- Case type
- Rimless
- Max pressure
- 41,500 psi, SAAMI transducer
- Eff. range
- 75 yd
- Max range
- 2850 yd
- Recoil
- 15.2–16.5 ft·lb
- Subsonic
- Capable
Introduced by Winchester Ammunition
Ballistics
Published velocity/energy data isn't available for .45 Winchester Magnum. Parent case: .45 ACP.
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 · verified| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 11.48 | 0.452 | ✓ |
| Neck ⌀ | 12.01 | 0.473 | ✓ |
| Shoulder ⌀ | n/a | ||
| Shoulder angle | n/a | ||
| Base ⌀ | 12.09 | 0.476 | ✓ |
| Rim ⌀ | 12.19 | 0.480 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.24 | 0.049 | ✓ |
| Neck length | n/a | ||
| Case length | 30.43 | 1.198 | ✓ |
| Overall length | 40.01 | 1.575 | ✓ |
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. .45 Winchester Magnum is highlighted below.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
Suitable powders
4 reloading powders listed for .45 Winchester 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 .45 Winchester Magnum
Lineage
Connected reference
History
Introduced in 1979 by Winchester for Wildey Moore's gas-operated Wildey pistol. The cartridge offered a semi-automatic alternative to large-frame revolvers for hunting. The LAR Manufacturing Grizzly Win Mag also chambered it. Factory ammunition is still produced by Winchester but in limited quantities. The cartridge's followers are primarily handgun hunters who prefer the semi-automatic platform.
FAQs
- What twist rate does .45 Winchester Magnum use?
- .45 Winchester Magnum typically uses a 1:16 twist rate.
- What bullet diameter is .45 Winchester Magnum?
- .45 Winchester Magnum uses a 0.452″ (11.481 mm) diameter bullet.
- Is .45 Winchester Magnum still in production?
- .45 Winchester Magnum is active; typical availability is limited.
- What is .45 Winchester Magnum used for?
- .45 Winchester Magnum is primarily used for hunting, self defense.
- What is .45 Winchester Magnum based on?
- .45 Winchester Magnum is derived from the .45 ACP case.
- What are the best powders for .45 Winchester Magnum?
- Reloading powders commonly listed for .45 Winchester Magnum include N350, Vihtavuori 3N37, N110, N105.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 18 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
