Sellier & Bellot Exergy Blue Bullet, Rifle Ammunition, 308 Winchester, 165 Grains, Lead Free Tipped Boat Tail, 20 Rounds per Box, 240 Rounds per Case SB308XA New generation lead free bullets. Modern, highly efficient design incorporating a boat-tail base with a new, pointed tip for a flat trajectory and maximum retained energy. Blue plastic tip enhances expansion at all ranges while the solid copper construction maximizes weight retention.