Pistol · SAAMI

.38 ACP

.38 Auto.38 Automatic Colt Pistol9x23mmSR

Original John Browning semi-auto pistol cartridge for the Colt 1900 and Model 1902.

Caliber
0.356″ · 9.042 mm
Introduced
1900
Case
Semi-Rimmed
Primary use
Military, Self Defense
Status
Discontinued
Velocity1,040–1,100 fps
Energy300–349 ft·lb
Typical grains130 gr
Identity
Introduced
1900
Type
Pistol
Origin
United States
Inventor
John Browning
Manufacturer
Colt, Winchester
Standard
SAAMI
Status
Discontinued
Availability
Collector
Build
Case capacity
16 gr H₂O
Twist (typical)
1:16
Primer
Small Pistol
Case type
Semi-Rimmed
Pressure & range
Max pressure
26,500 psi
Eff. range
50 yd
Max range
100 yd
Recoil
2.5–4 ft·lb
Subsonic
Capable

Ballistics

Representative trajectory · 25 yd zero0–200 yd
25 yd · zero0″−50″50″ drop @ 200 yd0100200Open in Ballistic Compare ↗
Parent case

Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).

Performance

Best for TargetCCI CCI Blazer130 gr · FMJ · 1,280 fpsBuy now →

Buy links open .38 ACP 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.

SAAMI · verified
Measuremmin
Bullet ⌀9.040.356
Neck ⌀9.750.384
Shoulder ⌀n/a
Shoulder anglen/a
Base ⌀9.750.384
Rim ⌀10.310.406
Belt ⌀n/a
Rim thickness1.270.050
Neck lengthn/a
Case length22.860.900
Overall length32.511.280

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 ACP is highlighted below.

Factory loads

In production — 3 active loads across 3 brands. Top 15 shown · see all 20 →.

BrandLoadGrainBulletFPSft·lbBC
CCICCI Blazer130FMJ1,280473
Sellier & BellotFMJ Service130FMJ1,040312
FiocchiFMJ Service130FMJ1,040312
GecoGeco Standard130FMJ1,280473
DWMDWM Standard130FMJ1,280473
GrafStandard130FMJ1,040312
DoubletapFMJ130FMJ1,040312
Remington-UMCFMJ130FMJ1,040312
WinchesterFMJ Original130FMJ1,040312
Western Cartridge Co.FMJ130FMJ1,040312
WinchesterStandard130FMJ1,040312
WolfFMJ130FMJ1,040312
ArmscorFMJ130FMJ1,040312
PPUFMJ130FMJ1,040312
FiocchiClassic130FMJ1,040312

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 .38 ACP

12 models in the database chamber .38 ACP. Browse all →

Various Spanish Astra 400 9mm Largo 5.9-inchAstra-Unceta Astra 400Astra-Unceta Astra 400 Model 1921 9mm LargoAstra Astra 400 9mm Largo 6-inchColt Colt Model 1902 Military .38 ACP 6-inchColt M1902 MilitaryColt M1902 Sporting .38 ACPColt M1902 Military .38 ACPWebley & Scott Webley-Fosbery Automatic Revolver .455 6-inchWebley & Scott Webley-Fosbery Automatic RevolverColt M1900 .38 ACPWebley Fosbery .455 Webley

Lineage

Immediate parent
Root — no documented parent
Direct descendants (2 · 4 total)
Family TreeOpen .38 ACP in the interactive cartridge family tree

Connected reference

History

Developed by John Browning for Colt's first semi-automatic pistols (Model 1900, 1902, 1903). The cartridge was the basis of early US military semi-auto trials before the .45 ACP was adopted. In 1929, Colt introduced the .38 Super as a higher-pressure version of the .38 ACP for the M1911 platform. The .38 ACP is now a collector cartridge associated with early Colt semi-automatics.

FAQs

What twist rate does .38 ACP use?
.38 ACP typically uses a 1:16 twist rate.
What bullet diameter is .38 ACP?
.38 ACP uses a 0.356″ (9.042 mm) diameter bullet.
Is .38 ACP still in production?
.38 ACP is discontinued; typical availability is collector.
What is .38 ACP used for?
.38 ACP is primarily used for military, self defense.

Sources & provenance

Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 3 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →