.40 S&W Ammo Overview

The .40 Smith & Wesson represents a purpose-built law enforcement cartridge that found widespread civilian adoption. Developed in 1990 as a joint venture between Smith & Wesson and Winchester, it was designed to offer near-10mm Auto performance in a more manageable package. The cartridge delivers substantial power while remaining controllable in duty-sized handguns.

While many law enforcement agencies have transitioned back to 9mm, the .40 S&W maintains a dedicated following among civilian shooters who appreciate its balance of power and practical shootability. Modern ammunition developments have kept it relevant, offering enhanced performance through improved bullet design and optimized loadings. The cartridge continues to serve effectively in defensive, competitive, and duty roles.

What .40 S&W Does Best

Personal Defense

The .40 S&W excels in defensive applications, delivering substantial energy and proven terminal performance. Modern defensive ammunition provides reliable expansion and adequate penetration, while the cartridge's moderate recoil allows for good shot placement in proper defensive scenarios. The availability of quality defensive loads from major manufacturers ensures reliable performance for personal protection.

Law Enforcement

Despite recent trends toward 9mm, the .40 S&W remains effective in law enforcement roles. Its ability to perform through intermediate barriers while maintaining good accuracy makes it suitable for duty use. The cartridge's power-to-recoil ratio, while higher than 9mm, remains manageable with proper training, and its terminal performance is well-documented through extensive field use.

Competition

In competitive shooting, particularly USPSA and IDPA, the .40 S&W offers advantages in power factor calculations. While more challenging to shoot than 9mm, skilled competitors can leverage its power factor benefits while managing the increased recoil. The cartridge's widespread availability and proven reliability make it a practical choice for competition use.

Popular Manufacturers

Premium Defensive

• Federal: HST and Hydra-Shok
• Speer: Gold Dot
• Hornady: Critical Duty/Defense
• Winchester: PDX1 Defender
• Sig Sauer: V-Crown

Practice/Training

• Federal: American Eagle
• Winchester: White Box
• Remington: UMC
• Blazer: Brass and Aluminum
• Sellier & Bellot: FMJ Training

.40 S&W History

The .40 S&W emerged from the FBI's search for an effective law enforcement cartridge following the 1986 Miami shootout. After briefly adopting the 10mm Auto, the FBI found that a reduced-power load better suited their needs. Smith & Wesson and Winchester collaborated to create a shortened 10mm cartridge that would function in modified 9mm-sized platforms.

Following its introduction in 1990, the .40 S&W gained rapid acceptance among law enforcement agencies. Its ability to deliver effective terminal performance while remaining controllable in duty-sized handguns led to widespread adoption. The cartridge became the dominant law enforcement round through the 1990s and early 2000s.

Recent developments in 9mm ammunition technology, combined with a focus on higher capacity and shooter comfort, have led many agencies to transition back to 9mm. However, the .40 S&W remains popular among civilian shooters and some law enforcement agencies. The cartridge's proven effectiveness and widespread availability ensure its continued relevance in the defensive handgun market.

Today, the .40 S&W represents a mature cartridge with extensive field experience and a wide variety of proven loads. While it may have peaked in law enforcement use, it maintains a strong position as a practical defensive cartridge for those willing to manage its increased recoil in exchange for enhanced terminal performance.