Rifle · SAAMI
.38-55 Winchester
Classic black-powder era cartridge still popular in cowboy action shooting and single-shot rifle competition.
- Caliber
- 0.377″ · 9.576 mm
- Introduced
- 1884
- Case
- Rimmed
- Primary use
- Hunting, Target
- Status
- Active
- Introduced
- 1884
- Type
- Rifle
- Origin
- United States
- Inventor
- Ballard
- Manufacturer
- Winchester, Marlin
- Standard
- SAAMI
- Status
- Active
- Availability
- Limited
- Case capacity
- 52 gr H₂O
- Twist (typical)
- 1:18
- Primer
- Large Rifle
- Case type
- Rimmed
- Max pressure
- 30,000 psi
- Eff. range
- 200 yd
- Max range
- 400 yd
- Recoil
- 3.5–5.5 ft·lb
- Subsonic
- Capable
Ballistics
Published velocity/energy data isn't available for .38-55 Winchester.
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 ⌀ | 9.58 | 0.377 | ✓ |
| Neck ⌀ | 9.96 | 0.392 | ✓ |
| Shoulder ⌀ | n/a | ||
| Shoulder angle | n/a | ||
| Base ⌀ | 10.69 | 0.421 | ✓ |
| Rim ⌀ | 12.85 | 0.506 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.60 | 0.063 | ✓ |
| Neck length | n/a | ||
| Case length | 52.96 | 2.085 | ✓ |
| Overall length | 63.75 | 2.510 | ✓ |
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. .38-55 Winchester is highlighted below.
Factory loads
Being verified
Advertised FPS, energy, and BC are withheld until loads clear verification.
Suitable powders
3 reloading powders listed for .38-55 Winchester, 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 .38-55 Winchester
12 models in the database chamber .38-55 Winchester. Browse all →
Lineage
Connected reference
History
Developed by Ballard in 1884, adopted by Winchester and Marlin for their rifles. Popular in Schuetzen target shooting and hunting through the late 19th and early 20th centuries. The cartridge survived into the smokeless era with reduced loads, remaining popular with cast-bullet enthusiasts and cowboy action shooters. The parent case for the .375 Winchester.
FAQs
- What twist rate does .38-55 Winchester use?
- .38-55 Winchester typically uses a 1:18 twist rate.
- What bullet diameter is .38-55 Winchester?
- .38-55 Winchester uses a 0.377″ (9.576 mm) diameter bullet.
- Is .38-55 Winchester still in production?
- .38-55 Winchester is active; typical availability is limited.
- What is .38-55 Winchester used for?
- .38-55 Winchester is primarily used for hunting, target.
- What are the best powders for .38-55 Winchester?
- Reloading powders commonly listed for .38-55 Winchester include H322, IMR 3031, H380.
Sources & provenance
- Standard SAAMI — SAAMI cartridge & chamber drawing — .38-55 Winchester archived
- 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 Winchester Ammunition — Power-Point rifle ammunition — 358 Winchester, symbol X3582 · grain_ballistics, representative_gun
- Manufacturer Black Hills Ammunition — .38-55 — Authentic Cowboy Action · grain_ballistics, representative_gun archived
- Manufacturer Buffalo Bore Ammunition — Heavy 38-55 Winchester Rifle Ammunition — Item 11C/20 · grain_ballistics, representative_gun archived
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 28 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →