Smokeless Powder, Black Powder, Primers, and Fuses ship from our warehouse with other products. This ensures no more than one Shipping Charge and one HazMat Charge per order (unless you also order products that Ship Separately from MidwayUSA or our Suppliers). Each order is limited to no more than 25 pounds of Black Powder, and no more than 66 pounds each of Smokeless Powder, Primers, or Fuse. Smokeless Powder, Black Powder, Primers, and Fuses are considered hazardous materials, incur HazMat Charges, and can only ship ground freight within the continental U.S. Due to safety considerations and legal/regulatory reasons, Smokeless Powder, Black Powder, Primers, and Fuses cannot be returned.
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 4227 is the Magnum Pistol Powder in the IMR lineup. If it says Magnum, IMR 4227 is the choice for true magnum velocities and performance. In rifles this powder delivers excellent velocity and accuracy in such cartridges as the 22 Hornet and 221 Fireball.
- 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.
IMR 4227 IMR Legendary Powders is a line of smokeless powders which are popularly used in sporting and military/police firearm cartridges. The initials ‘IMR’ stand for Improved Military Rifle powder
First powder plant
The French revolution caused E.I. DuPont de Nemours and Company to migrate to the United States in 1802. He built a factory to produce gunpowder near the site of Eleutherian Mills in Newark, Delaware. Today that site has been repurposed as the Hagley Museum and Library. DuPont’s first product at the site was blackpowder. DuPont powders were instrumental in helping to build the infrastructure of nations world with
They were vital to the mining and construction industries until replaced by more modern explosives. DuPont became a major producer of Dynamite and eventually developed many other products lines.
The line of improved military rifle powder came into existence in the 1920s. It consisted of nitrocellulose, dinitrotoluene (DNT), graphite, and a small amount (0.6%) of diphenylamine (stabilizer). Potassium sulfate is added to decrease the amount of muzzle flash. Cartridges loaded with this powder include .30-06 Springfield and 7.92 x 57mm Mauser.
DuPont began production of the IMR line of smokeless powders across the river from the Wilmington Plant at Carney’s Point, New Jersey in 1892. The first powders were called “MR” for Military Rifle powder.
In the 1920s these powders were improved and the name was changed to IMR. Various different powder are produced and are given numbers to distinguish them. The different types of powder typically have different burning rates. Due to the construction of metallic cartridges, different amounts of powder of different burning speeds are used to obtain optimum performance and accuracy.
Due to the increased demand for these powders which resulted from World War I an additional plant was constructed in Valleyfield, Canada which remains the primary source of IMR powders today. During World War II up to 1,000,000 pounds of powder was being shipped per day.
IMR Legendary Powders
- Rifle powders
- 4007 SSC
- 8208 XBR
- Handgun powders
- Trail Boss
- Shotgun powders