Winchester Autocomp Smokeless Powder 1 Lb by HODGDON , IMR & WINCHESTER AUTOCOMP is extremely fine in the 38 Super, 9mm, 45 ACP and 40 S&W race guns. It’s just the perfect burning speed to feed the compensators with a higher volume of gas. With AUTOCOMP competitors get off faster shots with minimal muzzle flash, it’s a winner. Grain shape is flat ball.
