These bullets deliver consistent performance. The Ballistic Tip Varmint's ultra-thin jacket mouth and lead core assures expansion at either end of the velocity scale. The uniform, gradual thickening of the jacket wall at the bullet's mid-section is designed to keep this bullet together until impact at any velocity. The heavy jacket base prevents bullet deformation during firing. Nosler's Solid Base® boat tail design, combined with the polycarbonate tip, increases long-range efficiency. .6mm, .243" diameter. Per 250.