To begin, IMR 4955 Enduron is a versatile, match-grade propellant with a mid-range burn speed that is in between IMR4451 and IMR7977. IMR 4955 Enduron is an extruded powder and provides top performance for big game cartridges like 25-06, 270 Winchester, 280 Remington, and 300 Win Mag, among other cartridges.
The main features of the Enduron series are copper fouling eliminator, insensitivity to temperature changes, ideal loading density, and being environmentally friendly.
IMR 4955 Enduron performs comparably to Hodgdon H4831 but charge weights are materially different.
Available in 1-LB and 8-LB containers.
THE IMR STORY
To begin, the DuPont Corporation allowed for the creation of The IMR brand under its umbrella. In fact, E. I. DuPont arrived in America in 1800 determined to make improved gunpowder and, by 1802, was producing gunpowder in a new plant along the Brandywine River in Wilmington, Delaware (this plant morphed into what is today the GOEX brand of black powder).
DuPont had historically been a major supplier of military propellants long before becoming one of the handloader’s favorite powders. First used in battle in 1805 by the United States naval forces against pirates off the coast of Algiers, DuPont supplied more than 80% of Allied Forces powder needs in World War I. In WW II ammunitions used every two weeks were equivalents to those used in the entirety of WW I. An incredible 2.5 billion pounds of smokeless propellants was manufactured by DuPont for Allied Forces in World War II due to this demand.
The IMR brand was first introduced under DuPont in the 1930s. IMR is an acronym for Improved Military Rifle. The first IMR reloading powders included ever-popular favorites IMR3031 (1934), IMR4064 (1935), and IMR4350 (1940). Each of these is still favorites with handloaders today! The IMR series of handloading powders were the only choice to wring full performance out of rifle calibers. For this reason, the IMR brand powders truly are Legendary products.
Time does not stand still and neither does the IMR brand. New technology allows for positive changes to versions of the traditional IMR burn speeds to be introduced although the brand continues to be a favorite of handloaders everywhere. These improved powders, identified by the “Enduron” sub-branding, offer improved temperature stability and an additive that removes copper bullet jacket fouling as you shoot. The Enduron powders are the first to offer all these features at the same time. The Enduron powder line continues to bring new burn rate offerings to the handloader.
Even in the early days, DuPont focused on innovation – offering “any quantity of powder as good or better than any available”. IMR constantly focuses on innovation nowadays. Originally a line of rifle powders the IMR brand has been expanded to include powders for use in handguns, shotshell,s and muzzleloaders. For 2017, IMR introduced five new pistol and shotshell powders. The IMR brand commitment to bring new and legendary powders to the handloader is a never-ending process.
Keep gunpowder products out of the reach of children. Handle with care. Do not store with combustibles.
Hodgdon® Powder, IMR® Powder, and Winchester® Powder expressly disclaim any and all warranties with respect to any and all products sold or distributed by them, the safety or suitability thereof, or the results obtained including, without limitation, any implied warranty of merchantability or fitness for a particular purpose and/or any other warranty.
Buyers and users assume all risk, responsibility, and liability whatsoever for any and all injuries (including death), losses or damages to persons or property (including consequential damages), arising from the use of any product or data, whether or not occasioned by the seller’s negligence or based on strict liability or principles of indemnity or contribution.
Store gunpowder products in a cool, dry place. Keep gunpowder products away from heat, open flame, and sparks.
Avoid impact and friction. Do not smoke when handling any gunpowder products.
Always wear ear and eye protection when handling, loading, and firing firearms.
Also, Wash your hands thoroughly after exposure. Read safety instructions on the packaging before use. Never mix any two powders regardless of type, brand, or source. Never substitute any use nitrocellulose-based smokeless powder for Black Powder or any Black Powder substitute.
In conclusion, never use nitrocellulose-based smokeless propellant powder in muzzleloading firearms. Use the data provided with Hodgdon, IMR, and Winchester powders only. For all powders, use only the components shown.