Doubletap Ammunition .40 S&W 155 Grain Hollow Point Pistol Ammo 20 Rounds. 100percent weight retention and exceptional expansion make this an awesome mid-weight pairing for your 40 S&W Boasting 14" of penetration with .86" of expansion; this load is a very effective option for CCW and self defense. Specifications for Doubletap Ammunition .40 S&W 155 Grain Hollow Point Pistol Ammunition: Manufacturer: Doubletap Ammunition Caliber: .40 S&W Number of Rounds: 20 Bullet Type: Hollow Point (HP) Bullet Weight: 155 grain Cartridge Case Material: Brass Application: Target Package Contents: Doubletap Ammunition .40 S&W 155 Grain Hollow Point Pistol Ammunition What is Doubletap Ammunition .40 S&W 155 Grain Hollow Point Pistol Ammunition good for? The manufacturer suggests that it is suitable for target.Doubletap Ammunition 40155X: .40 S&W 155 Grain Hollow Point Pistol Ammo 20 Rounds