Smith & Wesson M&P 5.7

What Is the S&W M&P 5.7?

The M&P 5.7 is Smith & Wesson's entry into the 5.7x28mm pistol market — a caliber originally developed by FN for military and law enforcement use and now gaining significant traction among civilian shooters. The M&P platform brings S&W's legendary ergonomics, reliability, and aftermarket support to this high-velocity, low-recoil cartridge.

Why 5.7x28mm?

The 5.7x28mm cartridge is uniquely suited to suppressed use. Its small-diameter, high-velocity projectile produces significantly less blowback than pistol calibers like 9mm or .45 ACP when running suppressed, and subsonic loads are readily available. The result is one of the softest-shooting, suppressor-friendly pistol calibers available. It's the same round that powers the FN PS90 carbine, meaning 5.7x28mm ammo is increasingly available and competitively priced.

Key Features

22+1 capacity — The M&P 5.7 ships with a flush-fit 22-round magazine — among the highest capacity of any semi-auto pistol in a standard form factor.

Optics-ready slide — The M&P 5.7 features a direct-mount optics cut compatible with common red dot footprints. No adapter required for most popular micro red dots.

Threaded barrel option — Available with a 5/8-24 threaded barrel for suppressor attachment. The 5.7x28mm cartridge's subsonic loads make this one of the most effective suppressor-host pistols available.

Suppressor Compatibility in 2026

As of January 1, 2026, the NFA tax stamp for suppressors was eliminated. A suppressor purchase now requires only a standard background check — no additional tax, no extended wait. The M&P 5.7 with a threaded barrel and a quality 5.7x28mm suppressor is one of the most capable and controllable suppressed pistol setups available.

How Does the M&P 5.7 Compare to the FN Five-seveN?

The FN Five-seveN is the original civilian 5.7x28mm pistol and remains a benchmark for the caliber. The M&P 5.7 competes directly — it offers a more ergonomic grip for most shooters, a lower bore axis, and broader aftermarket support through the M&P ecosystem. The Five-seveN holds a slight edge in historical reputation and civilian ammunition compatibility, but the M&P 5.7 is the more accessible and versatile platform for most buyers.

FAQ

What caliber is the S&W M&P 5.7?
The M&P 5.7 is chambered in 5.7x28mm — the same cartridge used in the FN Five-seveN pistol and FN PS90 carbine.

Does the S&W M&P 5.7 have a threaded barrel?
Yes — a threaded barrel variant is available. Thread pitch is 5/8-24, standard for 5.7x28mm suppressors.

Is the 5.7x28mm good for home defense?
Yes. The 5.7x28mm offers low recoil, high capacity, and quality expanding ammunition options. Its high velocity produces good terminal performance with the right load selection.

How does the M&P 5.7 compare to the FN Five-seveN?
Both shoot the same 5.7x28mm cartridge. The M&P 5.7 offers M&P ergonomics and a larger aftermarket; the FN Five-seveN has a longer track record in the caliber. Both are excellent choices.