40 S&W Brass Cases by Starline - 100 Pieces New Starline .40 (40 S&W) Brass Case The .40 S&W is basically a short version of the 10mm Auto that utilizes the Small Pistol primer. This cartridge quickly became a favorite among Law Enforcement, target shooters, and plinkers due to... MSRP: Was: Now: $25.99