Design Philosophy
The 5.7x28mm was originally developed for FN's P90 personal defense weapon and Five-seveN pistol, designed around a small-diameter, high-velocity bullet concept intended to defeat body armor in military and law enforcement applications while generating very mild recoil. The 9mm, by contrast, is a much older, more traditional defensive cartridge relying on a larger diameter bullet at moderate velocity for reliable expansion and stopping power.
Recoil and Shootability
This is the 5.7x28's signature advantage. It generates dramatically less recoil than the 9mm, making it remarkably easy to shoot accurately and quickly, even for recoil-sensitive shooters or those with limited hand strength. Pistols like the FN Five-seveN are also often praised for higher magazine capacity, frequently holding 20 rounds or more, giving shooters a meaningful edge in both control and capacity compared to a similarly sized 9mm pistol.
Terminal Performance Debate
This is where opinions diverge sharply. The 9mm benefits from decades of extensive testing and refinement in defensive hollow-point technology, with loads like Federal's HST option in 124-grain JHP configuration representing a thoroughly proven, FBI-protocol-tested design. The 5.7x28, while capable of impressive penetration thanks to its high velocity, has a smaller selection of dedicated defensive hollow-point loads, such as Speer's Gold Dot 5.7x28 option in 40-grain configuration, and the ammunition testing and law enforcement adoption behind it, while growing, doesn't yet match the sheer volume of data behind 9mm defensive rounds.
Cost and Availability
The 9mm remains significantly more affordable and widely available, being the most common handgun cartridge in the world. The 5.7x28, while increasingly popular and more available than it once was, still commands a noticeable price premium per round and requires more deliberate sourcing, typically through online specialty retailers.
Pistol Selection
The 9mm offers an enormous selection of pistols across every size category, price point, and manufacturer. The 5.7x28 is still a more specialized cartridge, with a narrower (though growing) selection of compatible firearms, historically centered on FN's own pistol lineup, though other manufacturers have begun producing options as well.
Which Should You Choose?
If you want the widest firearm selection, the most affordable and available ammo, and a cartridge with an unmatched track record in defensive applications, the 9mm remains the smarter default choice for most shooters. If you specifically prioritize minimal recoil, high capacity, and enjoy shooting a genuinely unique and fun platform — and you're willing to pay a premium for ammo — the 5.7x28 offers a compelling, if pricier, alternative.
Both cartridges are available at the BulkAmmoToGo shop.