Lindcott Armory Revolver · SAAMI
.45 Auto Rim
Rimmed version of .45 ACP designed for use in revolvers without moon clips.
- Caliber
- 0.452″ · 11.481 mm
- Introduced
- 1920
- Case
- Rimmed
- Parent
- .45 ACP
- Primary use
- Self Defense, Target
- Status
- Active
- Introduced
- 1920
- Type
- Revolver
- Origin
- United States
- Inventor
- Peters Cartridge Company
- Manufacturer
- Peters, Winchester, various
- Standard
- SAAMI
- Status
- Active
- Availability
- Limited
- Case capacity
- 26.7 gr H₂O
- Twist (typical)
- 1:16
- Primer
- Large Pistol
- Case type
- Rimmed
- Max pressure
- 17,400 psi
- Eff. range
- 50 yd
- Max range
- 100 yd
- Recoil
- 3–5 ft·lb
- Subsonic
- Capable
Ballistics
Real trajectory computed from a representative load — Buffalo Bore Heavy 255 gr, 830 fps, BC 0.220 G1 · 25 yd zero.
| Range | Velocity | Energy | Drop (in) | Drop (MOA) |
|---|---|---|---|---|
| 0 yd | 830 | 390 | -0.9″ | — |
| 25 yd | 817 | 378 | 0.0″ | 0.0 |
| 50 yd | 804 | 366 | -2.4″ | -4.5 |
| 75 yd | 791 | 355 | -8.1″ | -10.3 |
| 100 yd | 779 | 344 | -17.3″ | -16.5 |
| 125 yd | 768 | 334 | -30.0″ | -22.9 |
| 150 yd | 756 | 324 | -46.5″ | -29.6 |
| 175 yd | 745 | 314 | -66.7″ | -36.4 |
| 200 yd | 734 | 305 | -90.9″ | -43.4 |
Point-mass G7/G1 drag model, standard atmosphere — within ~2% of reference solvers to 1000 yd; real barrels and conditions vary. Open in Ballistic Compare →
Performance
Buy links open .45 Auto Rim ammunition at Rivertown Munitions.
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 · verified| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 11.48 | 0.452 | ✓ |
| Neck ⌀ | 11.90 | 0.469 | ✓ |
| Shoulder ⌀ | n/a | ||
| Shoulder angle | n/a | ||
| Base ⌀ | 11.96 | 0.471 | ✓ |
| Rim ⌀ | 13.10 | 0.516 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 2.10 | 0.083 | ~ |
| Neck length | n/a | ||
| Case length | 22.84 | 0.899 | ✓ |
| Overall length | 32.25 | 1.270 | ~ |
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 Auto Rim is highlighted below.
Factory loads
In production — 17 active loads across 11 brands. Top 15 shown · see all 20 →.
| Brand | Load | Grain | Bullet | FPS | ft·lb | BC |
|---|---|---|---|---|---|---|
| Buffalo Bore | Heavy | 255 | SWC | 830 | 390 | 0.220 G1 |
| Buffalo Bore | Hard Cast WFNGC | 255 | Hard Cast | 950 | 511 | — |
| HSM Ammunition | Self Defense | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Doubletap | DT Defense | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Buffalo Bore | Heavy | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Buffalo Bore | Heavy | 255 | Hard Cast | 900 | 459 | — |
| Buffalo Bore | Standard | 230 | JHP | 900 | 414 | — |
| Armscor | Standard | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Cor-Bon | JHP | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Cor-Bon | DPX | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Black Hills | Match | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Sellier & Bellot | JHP | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Wolf | FMJ | 230 | Jacketed Hollow Point | 900 | 414 | — |
| Hornady | Custom XTP JHP | 230 | XTP JHP | 850 | 369 | — |
| Federal | American Eagle FMJ | 230 | FMJ | 830 | 352 | — |
Velocities are manufacturer-stated (test-barrel). Discontinued loads dimmed.
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 Auto Rim
12 models in the database chamber .45 Auto Rim. Browse all →
Lineage
Connected reference
History
Developed in 1920 by Peters Cartridge Company for the S&W M1917 and Colt M1917 revolvers — WWII-era service revolvers that had been chambered in .45 ACP using half-moon clips during WWI. The .45 Auto Rim allowed the M1917 revolvers to function as standard revolvers without requiring clips. Still produced today for shooters who prefer to load .45-caliber revolvers individually rather than using moon clips.
FAQs
- What twist rate does .45 Auto Rim use?
- .45 Auto Rim typically uses a 1:16 twist rate.
- What bullet diameter is .45 Auto Rim?
- .45 Auto Rim uses a 0.452″ (11.481 mm) diameter bullet.
- Is .45 Auto Rim still in production?
- .45 Auto Rim is active; typical availability is limited.
- What is .45 Auto Rim used for?
- .45 Auto Rim is primarily used for self defense, target.
- What is .45 Auto Rim based on?
- .45 Auto Rim is derived from the .45 ACP case.
Sources & provenance
- StandardSAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawingsarchived
- StandardC.I.P. — C.I.P. TDCC — Tables of Dimensions of Cartridges and Chambers
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 17 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →