The .40 Super is a heavy duty lengthened case similar to the .45 Auto cartridge but necked down to .40" caliber. Starline is a family owned business and prides itself on producing the highest quality brass case available. With a production process focused on quality not quantity, Starline makes the finest brass and has for more than 40 years out of their state-of-the-art manufacturing facility in Sedalia, MO. Mfg: Starline, Inc
