Differences between .40 S&W and .45 ACP
Contents
.40 S&W vs. .45 ACP[edit]
The .40 S&W and .45 ACP are two popular centerfire pistol cartridges with long histories of use in military, law enforcement, and civilian applications.[1][2] The .45 ACP is an older cartridge, designed by John Moses Browning in 1904, and is known for its use in the M1911 pistol.[3][4] The .40 S&W was developed in 1990 by Smith & Wesson and Winchester in response to the FBI's search for a cartridge with more power than the 9mm Parabellum but with more manageable recoil than the 10mm Auto.[5]
Both cartridges have proven to be effective for self-defense, though they achieve their performance through different approaches. The .45 ACP fires a heavier, larger-diameter bullet at subsonic velocities, while the .40 S&W fires a lighter, smaller-diameter bullet at higher velocities.[2]
Comparison Table[edit]
| Category | .40 S&W | .45 ACP |
|---|---|---|
| Designer | Smith & Wesson and Winchester | John Moses Browning |
| Year Designed | 1990 | 1904[3] |
| Bullet Diameter | .400 in (10.2 mm) | .452 in (11.5 mm)[3] |
| Typical Bullet Weight | 155–180 gr (10.0–11.7 g) | 185–230 gr (12.0–14.9 g) |
| Maximum Pressure (SAAMI) | 35,000 psi (241 MPa) | 21,000 psi (145 MPa) |
| Magazine[3] Capacity | Generally higher due to smaller cartridge diameter | Generally[1] lower due to larger cartridge diameter |
| Recoil | Often described as "sharp" or "snappy" | Often[1] described as a "push" |
[2] History and Development[edit]
The development of the .45 ACP was a direct result of the U.S. military's experiences during the Philippine-American War, where the .38 Long Colt was found to have inadequate stopping power. After the Thompson-LaGarde Tests of 1904 concluded that a .45 caliber projectile was most effective, John Browning developed the .45 ACP cartridge for his new semi-automatic pistol design, which would be adopted as the M1911. The standard[3] military load for the .45 ACP features a 230-grain bullet traveling at approximately 830 feet per second.
The .40[3] S&W cartridge was created in the aftermath of the 1986 FBI Miami shootout. The incident[5] prompted the FBI to seek a more potent handgun cartridge. The FBI's testing of a reduced-velocity 10mm Auto load provided the performance they desired without the harsh recoil of the full-power 10mm. Smith & Wesson and Winchester then designed a shorter cartridge that duplicated the ballistics of the FBI's 10mm load, which could fit in medium-frame handguns, resulting in the .40 S&W.
Ballistics and Performance[edit]
Ballistically, the two cartridges offer a trade-off between momentum and velocity. The .45 ACP relies on its larger diameter and heavier bullet to create a large wound channel. The .40[2] S&W, operating at a significantly higher pressure, fires its lighter bullets at higher speeds, resulting in a flatter trajectory. Muzzle energy for both cartridges is often comparable in many commercial loadings.
The felt[2] recoil of the two cartridges is subjective but generally distinct. The lower pressure of the .45 ACP is often reported to produce a slower, pushing recoil impulse. In contrast,[2] the higher pressure of the .40 S&W is frequently described as a sharper, "snappier" recoil.
Due to[1] its smaller diameter, the .40 S&W allows for a higher magazine capacity in a firearm of similar size compared to the .45 ACP. For example,[1] a standard Glock 22 in .40 S&W holds 15 rounds, while a Glock 21 in .45 ACP holds 13 rounds. This difference in capacity is a significant consideration for many shooters.[1]
References[edit]
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 "cyasupply.com". Retrieved December 20, 2025.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 "ammo.com". Retrieved December 20, 2025.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 "wikipedia.org". Retrieved December 20, 2025.
- ↑ "americanhunter.org". Retrieved December 20, 2025.
- ↑ 5.0 5.1 "pd-ammo.com". Retrieved December 20, 2025.
