The Pentagon line of rifle ammunition centers on a monolithic copper hollow point design carefully engineered for controlled opening on impact to maximize penetration while delivering optimal hydrostatic shock. These environmentally safe, lead-free projectiles deliver petal expansion to twice the bullet diameter. The Pentagon's higher velocities and greater impact energy than conventional composite bullets are credited to the monolithic copper bullet's lighter weight and the NovX patented 2-piece stainless steel cartridge case design. The net result is a defensive cartridge that is lighter to carry concealed, easier to shoot, provides for fast sight picture acquisition on follow-up shots through reduced muzzle flip, and superior terminal performance to quickly end defensive engagements.