IMR Enduron 8133 Smokeless Gun Powder

Production of IMR powders dates back over 200 years when the company was originally founded by E.I DuPont. Available for use in many reloading applications, the IMR series of powder is trusted by reloaders all across the globe.

IMR Enduron 8133 is the slowest burn rate in the Enduron family. Loading density is perfect for magnums, contributing to superb uniformity. This is a true magnum propellant yielding outstanding performance in 6.5-300 Weatherby, 264 Win Mag, 28 Nosler and 300 Rem Ultra Mag, among other cartridges. Loading density is perfect for magnums, nicely filling the case at maximum charges, contributing to superb uniformity and accuracy.

The main features of the Enduron series are copper fouling eliminator, insensitivity to temperature changes, ideal loading density and being environmentally friendly.

IMR 8133 performs comparably to Hodgdon Retumbo but charge weights are materially different.

Engineered Consistency for Precision Rifle Loads

Push your rifle’s accuracy further with IMR Enduron 8133, a modern propellant built for shooters who demand tight groups and repeatable ballistics. Enduron 8133 delivers uniform ignition and low standard deviations, helping reloaders achieve consistent velocities shot after shot. Whether you’re tuning match loads, developing a hunting round, or producing reliable training ammo, this powder gives you the repeatability that separates “good” from “great” performance on the range and in the field.

Enduron Technology Less Fouling, More Shooting

IMR’s Enduron chemistry was formulated to improve barrel life and reduce maintenance. Enduron 8133 burns cleanly, minimizing copper fouling and carbon deposits so barrels retain accuracy longer between cleanings. That cleaner operation means you spend more time shooting and less time scrubbing perfect for long practice sessions, extended hunting trips, or match prep where sustained accuracy matters.

Temperature Stability & Real-World Reliability

Designed with real shooters in mind, Enduron 8133 offers robust temperature tolerance, maintaining predictable pressures and velocities across everyday climate swings. When the mercury rises or drops, your point-of-impact stays more consistent so you can rely on your zero whether you’re shooting on a cool morning or under a hot afternoon sun. This stability makes Enduron 8133 a dependable choice for reloaders who demand performance in varied conditions.

Smooth Metering & Efficient Reloading

Reloaders appreciate Enduron 8133 for its excellent flow characteristics and uniform granule size. It meters smoothly through powder measures on both single-stage and progressive presses, delivering accurate charge weights and reducing batch-to-batch variation. If you produce high volumes of ammo or carefully work up precision loads, Enduron 8133 speeds the process and improves repeatability.

Why Choose IMR Enduron 8133:

• Clean-burning Enduron chemistry reduces copper and carbon fouling.

• Tight velocity spreads and consistent ignition for improved accuracy.

• Excellent temperature tolerance for real-world shooting conditions.

• Smooth, predictable metering for efficient reloading.

• Ideal for small- to medium-capacity rifle applications and precision loads.

Important Information:

• Do not exceed the loads displayed in the reloaders guide.
• Never mix any two powders regardless of type, brand, or source.
• Never substitute any smokeless powder for Black Powder or any Black Powder substitute.