What is the Difference Between 45 ACP and 45 GAP Pistols?

The main differences between .45 ACP and .45 GAP pistols are:

1. Cartridge Dimensions: The .45 ACP (Automatic Colt Pistol) has a larger cartridge size compared to the .45 GAP (Glock Auto Pistol). The .45 GAP is slightly shorter and has a smaller cartridge volume, allowing it to fit in pistols with a 9mm or .40 frame size.
2. Primer: The .45 GAP uses a small-pistol primer, while the .45 ACP uses a large-pistol primer.
3. Standard Pressure: The .45 GAP was designed to operate at a higher standard pressure compared to the .45 ACP, enabling it to achieve similar performance with a smaller cartridge volume.
4. Bullet Weights: Originally, the maximum bullet weight for the .45 GAP was 200 grains (13 g), but later developments allowed it to fire 230-grain (15 g) projectiles, as does the .45 ACP. However, this pushes the .45 GAP cartridge to its limits.
5. Firearms: The .45 ACP is used in larger, heavier pistols, while the .45 GAP is designed for smaller, more compact pistols. Some examples of .45 GAP pistols include Glock 37, Glock 39, and Springfield XD.
6. Ammo Availability and Cost: The .45 ACP is more popular and widely available, making it easier to find ammunition and resulting in lower prices. The .45 GAP is less common, which can make finding ammunition more difficult and expensive.

Despite these differences, the two calibers perform similarly in most pistols, delivering similar ballistic performance. However, personal preferences in terms of size, weight, and recoil will play a role in determining which caliber is more suitable for an individual.

Comparative Table: 45 ACP vs 45 GAP Pistols

The .45 ACP and .45 GAP are both .45 caliber cartridges, but they have some differences in terms of design, performance, and usage. Here is a table comparing the two:

The .45 GAP was designed by Glock to provide performance equivalent to the .45 ACP but with a shorter case, allowing it to be used in pistols with a 9mm or .40 frame size. Although the .45 GAP has a higher standard pressure, the .45 ACP has a lower functioning pressure, resulting in less recoil and potentially better accuracy. The .45 ACP offers superior stopping power compared to the .45 GAP. In terms of ammunition availability and cost, the .45 ACP is more readily available and generally cheaper, while the .45 GAP can be more difficult to find and may be more expensive.