The ProMag S&W SD40 50-round drum magazine is a high-capacity pistol magazine purpose-built for the Smith & Wesson SD40 in .40 S&W. If you run an SD40 and want extended capacity for the range, competition, or defensive practice, this drum mag transforms your platform from standard 10-15 round capacity to 50 rounds between reloads—a serious upgrade for shooters who value volume and reduced downtime.

ProMag magazines are manufactured in the USA with a focus on reliability and durability. The construction combines a proprietary DuPont Zytel-based polymer hybrid body with a steel upper magazine tower, engineered to handle repeated loading, feeding, and ejection cycles. The magazine spring is formed from heat-treated stainless steel and wound with precision; every assembly step is inspected and verified to maintain consistent quality across the production line.

The drum format means more rounds on tap without the bulk of stacking multiple single-stack mags—ideal for high-volume shooting sessions or training blocks where magazine changes eat into your range time. Like all ProMag magazines, this SD40 drum is backed by a lifetime guarantee against manufacturer's defects, so you can trust it will perform when you need it.

The ProMag S&W SD40 50-round drum magazine is a high-capacity pistol magazine purpose-built for the Smith & Wesson SD40 in .40 S&W. If you run an SD40 and want extended capacity for the range, competition, or defensive practice, this drum mag transforms your platform from standard 10-15 round capacity to 50 rounds between reloads—a serious upgrade for shooters who value volume and reduced downtime.

ProMag magazines are manufactured in the USA with a focus on reliability and durability. The construction combines a proprietary DuPont Zytel-based polymer hybrid body with a steel upper magazine tower, engineered to handle repeated loading, feeding, and ejection cycles. The magazine spring is formed from heat-treated stainless steel and wound with precision; every assembly step is inspected and verified to maintain consistent quality across the production line.

The drum format means more rounds on tap without the bulk of stacking multiple single-stack mags—ideal for high-volume shooting sessions or training blocks where magazine changes eat into your range time. Like all ProMag magazines, this SD40 drum is backed by a lifetime guarantee against manufacturer's defects, so you can trust it will perform when you need it.