Lindcott Armory Rifle · Military
11mm Beaumont
Black powder military cartridge for the Dutch Beaumont and Beaumont-Vitali repeating rifles; one of the last major military services using a large-bore black powder round..
- Caliber
- 0.4555″ · 11.57 mm
- Introduced
- 1871
- Case
- Rimmed
- Primary use
- Military service
- Status
- Discontinued
- Introduced
- 1871
- Type
- Rifle
- Origin
- Netherlands
- Inventor
- Edouard de Beaumont / Dutch military
- Standard
- Military
- Status
- Discontinued
- Availability
- Rare
- Primer
- Berdan Large Rifle
- Case type
- Rimmed
- Max pressure
- 18,000 psi
- Eff. range
- 400 yd
Ballistics
- Parent case
- —
Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).
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 ⌀ | 11.57 | 0.456 | · |
| Neck ⌀ | 11.92 | 0.469 | ~ |
| Shoulder ⌀ | — | — | |
| Shoulder angle | — | — | |
| Base ⌀ | 14.61 | 0.575 | · |
| Rim ⌀ | 16.66 | 0.656 | ~ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.50 | 0.059 | ~ |
| Neck length | — | — | |
| Case length | 50.97 | 2.007 | · |
| Overall length | 64.08 | 2.523 | · |
Missing a dimension for 11mm Beaumont? 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.
Reloading costestimate cost per round vs factory
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Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.
Firearms chambered in 11mm Beaumont
1 model in the database chamber 11mm Beaumont. Browse all →
Connected reference
History
Adopted in 1871 for the Dutch Beaumont single-shot rifle, and later used in the Beaumont-Vitali 8-round tubular magazine conversion. The Netherlands was one of the last major powers to field large-bore black powder military rifles before the transition to small-bore smokeless cartridges.
FAQs
- What bullet diameter is 11mm Beaumont?
- 11mm Beaumont uses a 0.4555″ (11.57 mm) diameter bullet.
- Is 11mm Beaumont still in production?
- 11mm Beaumont is discontinued; typical availability is rare.
Sources & provenance
- ReferenceGun Digest Books — Cartridges of the World (Frank C. Barnes) — 11mm Beaumont (Dutch, .43 Beaumont) · grain weights, bullet ⌀, velocity, year
- Secondarymilitaryrifles.com — M1871 & M1871/79 Beaumont · year, velocity, bullet ⌀archived
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →