Why did FBI stop using 10mm?

Answered by Cody Janus

The FBI made the decision to stop using the 10mm cartridge as their standard ammunition for most agents and units, with the exception of the Hostage Rescue Team (HRT) and Special Weapons and Tactics (SWAT) teams. This decision was made after the Firearms Training Unit (FTU) conducted extensive testing and evaluation of the cartridge.

One of the main reasons for the discontinuation of the 10mm was its recoil. The 10mm cartridge generates significant recoil, which can affect accuracy and follow-up shots. The FBI found that many agents, particularly those with smaller stature or less shooting experience, struggled to effectively control the recoil of the 10mm. This led to concerns about accuracy and the ability to rapidly fire follow-up shots, which are crucial in high-stress situations.

Another factor that contributed to the FBI’s decision was the availability and variety of ammunition. At the time, there were limited options for 10mm ammunition, and the FBI was not satisfied with the performance and consistency of the available rounds. This lack of reliable ammunition made it difficult to ensure consistent terminal ballistics and stopping power.

Additionally, the 10mm cartridge was deemed to have excessive penetration capabilities. In law enforcement scenarios, over-penetration can pose a significant risk to bystanders and innocent individuals. The FBI determined that the 10mm had a higher risk of over-penetration compared to other available cartridges, which raised concerns about collateral damage in real-world shooting incidents.

The FBI’s decision to discontinue the use of the 10mm cartridge for most agents and units was not taken lightly. It was based on extensive research, testing, and feedback from agents in the field. The goal was to find a cartridge that offered a balance of controllability, terminal ballistics, and reduced risk of over-penetration.

As a result, the FBI eventually replaced the 10mm with the .40 S&W (Smith & Wesson) cartridge. The .40 S&W was developed specifically to address the concerns raised by the 10mm. It offered similar ballistics to the 10mm but with reduced recoil, making it more manageable for a wider range of agents. The .40 S&W also had a wider selection of ammunition available, allowing the FBI to choose rounds that met their performance and consistency requirements.

The FBI stopped using the 10mm cartridge as their standard ammunition due to concerns about recoil, limited ammunition options, and excessive penetration capabilities. These factors led to the adoption of the .40 S&W cartridge, which offered a better balance of controllability, terminal ballistics, and reduced risk of over-penetration. The decision was based on extensive testing and feedback from agents in the field to ensure the best possible performance in real-world law enforcement scenarios.