Pistol · CIP · Not SAAMI standardized · CIP standardizedObsolete
.45 HP
.45 HP is a rimless straight-walled pistol cartridge of Austria origin.
- Caliber
- 0.452″ · 11.48 mm
- Introduced
- 1985
- Case
- Rimless
- Parent
- .45 ACP
- Primary use
- Self-Defense, Target
- Status
- Discontinued
- Obsolete
- Obsolete
- Introduced
- 1985
- Type
- Pistol
- Origin
- Austria
- Inventor
- Hirtenberger
- Manufacturer
- Hirtenberger
- Standard
- CIP · Not SAAMI standardized · CIP standardized
- SAAMI
- Not SAAMI standardized
- Obsolete
- Obsolete
- Status
- Discontinued
- Availability
- Rare
- Case capacity
- 24.1 gr H₂O
- Twist (typical)
- 1:16.0
- Primer
- Large Pistol
- Case type
- Rimless
- Max pressure
- 18,855 psi, CIP transducer
- Eff. range
- 50 yd
- Max range
- 250 yd
- Recoil
- 10.3–12.5 ft·lb
- Subsonic
- Capable
Ballistics
Velocity only, no drag model: no published ballistic coefficient is on file for .45 HP, so this is the shape gravity alone gives the advertised velocity. Drag would steepen it. The tool below solves real loads through their published G1 or G7 model.
Open in Ballistic Compare- Parent case
- .45 ACP
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.
CIP TDCC · approximate| 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 ⌀ | 12.05 | 0.474 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.24 | 0.049 | ✓ |
| Neck length | n/a | ||
| Case length | 21.80 | 0.858 | ✓ |
| Overall length | 31.40 | 1.236 | ✓ |
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 HP is highlighted below.
Missing a dimension for .45 HP? 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
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.
Lineage
Connected reference
History
The .45 HP is a straight rimless handgun cartridge originating in Austria.
FAQs
- What twist rate does .45 HP use?
- .45 HP typically uses a 1:16.0 twist rate.
- What bullet diameter is .45 HP?
- .45 HP uses a 0.452″ (11.48 mm) diameter bullet.
- Is .45 HP still in production?
- .45 HP is discontinued; typical availability is rare.
- What is .45 HP used for?
- .45 HP is primarily used for self-defense, target.
- What is .45 HP based on?
- .45 HP is derived from the .45 ACP case.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →
