Promag Thompson 45acp 40rd Drum Blk

The Pro Mag Thompson 45 ACP 40-round drum magazine brings serious capacity to your Auto-Ordnance Thompson .45 ACP carbine. If you shoot competition, tactical training, or just love running high-capacity mags at the range, this drum transforms your Thompson from a historical reference into a practical, fun-to-shoot platform. The 40-round capacity means fewer reloads and more trigger time—exactly what you need when you're pushing rounds downrange.

Built for reliability, the drum housing is molded from a proprietary DuPont Zytel-based polymer engineered to handle the demands of repeated loading and firing. The injection-molded follower keeps rounds feeding smoothly, while the heat-treated stainless steel spring delivers consistent pressure cycle after cycle. It's made right here in the USA, which means the quality control and materials are held to real standards, not just cost-cutting minimums.

Drum magazines for the Thompson aren't as common as stick mags, so if you own a .45 ACP Thompson carbine and want to maximize fun and capacity, this is the straightforward choice. The black finish matches modern tactical setups while respecting the classic lines of the gun itself.

Key Features

• 40-round capacity for extended shooting sessions without frequent reloads
• Proprietary DuPont Zytel polymer housing for durability and reliability
• Heat-treated stainless steel spring for consistent feeding
• Injection-molded follower ensures smooth round advancement
• Made in USA with quality construction standards
• Black finish

Specifications

Frequently Asked Questions

Will this 40-round drum work with my Thompson .45 ACP?

Yes, this Pro Mag drum is designed specifically for the Auto-Ordnance Thompson .45 ACP Carbine. Verify your rifle matches that platform before ordering.

What's the magazine made from?

The drum housing is constructed from a proprietary DuPont Zytel-based polymer, which provides durability and reliability. The spring is heat-treated stainless steel, and the follower is injection molded for smooth feeding.

Is this magazine made in the USA?

Yes, Pro Mag manufactures this drum magazine in the USA.

Why choose a drum magazine over standard magazines?

A 40-round drum cuts down on reload frequency, making it ideal for range sessions, tactical training, or competition where you want extended shooting without stopping to swap magazines.