1. Cartridge Dimensions:
- .32 ACP:
- Bullet Diameter: 7.92mm (0.312 inches)
- Case Length: 17.3mm (0.680 inches)
- Overall Length: 23mm (0.910 inches)
- .32 S&W Long:
- Bullet Diameter: 7.92mm (0.312 inches)
- Case Length: 23.3mm (0.918 inches)
- Overall Length: 29.4mm (1.158 inches)
2. Chamber Pressure:
- .32 ACP: Typically operates at a chamber pressure of 100–105 megapascals (MPa) or 14,500–15,230 pounds per square inch (psi).
- .32 S&W Long: Generally has a lower chamber pressure of 75–80 MPa (10,915–11,603 psi).
3. Bullet Weights:
- .32 ACP: Bullets typically range in weight from 60 to 85 grains.
- .32 S&W Long: Bullets commonly weigh between 98 to 108 grains.
4. Specific Uses:
- .32 ACP: Initially designed as a self-defense cartridge for concealable pistols and pocket guns, .32 ACP is frequently used in semi-automatic pistols. It is known for its low recoil and is still popular for concealed carry and personal protection.
- .32 S&W Long: Primarily intended for small revolvers and derringers, .32 S&W Long offers a slightly improved performance over .32 ACP in terms of muzzle velocity and energy due to its longer case. However, it is not as commonly used as .32 ACP in semi-automatic pistols.
In summary, while both cartridges share a similar bullet diameter of 7.92mm (0.312 inches), they differ in case dimensions, chamber pressures, bullet weights, and their preferred applications. .32 ACP is more suitable for semi-automatics and is more popular for self-defense, whereas .32 S&W Long finds its niche in small revolvers and derringers.
