.38-45 ACP

The .38-45 ACP is a fascinating wildcat cartridge with a unique historical background tailored primarily for competitive shooters and custom firearms enthusiasts. Originating in the late 1960s, the .38-45 ACP was developed by renowned gunsmith Bo Clerke. The idea behind its creation was to merge the reliability and case capacity of the .45 ACP cartridge with the superior ballistic characteristics of the 0.357-inch bullet, commonly used in .38 caliber loads. This was achieved by necking down a standard .45 ACP case to accept a .355–.357 inch bullet, resulting in a bottlenecked design. The .38-45 ACP is also sometimes referred to as the .38-45 Clerke, and it quickly gained a following among competitive shooters looking for an edge in accuracy and reduced recoil, particularly in action shooting sports like IPSC and NRA Bullseye competitions.

For ammunition reloaders, the .38-45 ACP represents an excellent platform for experimentation and customization. Due to its wildcat status, commercial ammunition and off-the-shelf reloading dies are not widely available, making it an appealing choice for veteran reloaders seeking performance advantages through hand-tailored loads. The bottlenecked shape of the cartridge enhances feeding reliability in semi-automatic pistols, particularly 1911-style frames which are easily modified for this caliber. The .38-45 ACP excels in target shooting applications, delivering flat trajectories, mild recoil, and consistent accuracy, making it well-suited for high-volume practice, matches, and even steel challenge disciplines. Although largely intended for paper targets and steel plates, the versatility of the cartridge makes it a viable option for those who enjoy custom caliber development.

When discussing target species, it’s important to remember that the .38-45 ACP is primarily designed for target shooting and competition rather than hunting or self-defense. Its energy and terminal performance are best suited for range use, where control and precision are more valuable than sheer stopping power. That said, the caliber’s energy levels are notably higher than the .38 Super or standard 9mm Luger loads, placing it comfortably above them for paper and steel targets. Due to its velocity and exceptional accuracy, some reloaders have explored its viability as a small game or varmint cartridge when loaded with appropriate bullets, but care should be taken due to bullet expansion and penetration characteristics.

Typical bullet weights for the .38-45 ACP range from 115 grains up to around 147 grains, with many reloaders favoring 125- to 135-grain projectiles for optimal balance between velocity and controllability. Using hollow point or full metal jacket bullets with profiles intended for 9mm ensures reliable feeding in modified 1911 magazine wells. The cartridge case itself, modified from standard .45 ACP brass, retains durability for multiple reloads, and reloading data often recommends moderate-to-slow-burning pistol powders for safe pressure management and velocity consistency. The .38-45 ACP pushes 125-grain bullets to velocities approaching 1,300 feet per second, delivering a flat trajectory ideal for serious target shooters. Ultimately, for the experienced ammunition reloader, the .38-45 ACP offers a unique combination of handloading challenge, competitive advantage, and historical cachet—a wildcat rewarding both to build and to shoot.