NEW SPG TROPIC cast bullet lube for black & smokeless powder! This is a new formulation that will hold up under higher temperatures while maintaining the accuracy expected of Classic SPG Cast Bullet Lube. SPG has been a consistent top performer and is still the most popular lube on the market. A long time favorite by many and used to win many National, State and local matches. The standard lube that all other lubes are compared against. For black powder and smokeless loads.