Home Forums Hunting & Shooting Ask The Gunwriters Must be bored to ask this, but curious.

Was wondering if there is any significance to the numbering system used on powders. As an example, we all know that the .30-06 Springfield stands for .30 caliber- developed in 1906. .257 Roberts named after it's wildcatter, 7x57 7mm bore 57mm length. Now is there any meaning to say IMR-3031? Does the 3031 have any meaning or did DuPont just grab it out of the air. I know Varget stands for Varmint/ Target and H-380 for the load in the .22-250. But what about the numbered powders. How about the new IMR-8133 or 4166. Is it something to do with the chemical formula? I know it's a crazy question, just curious. Any takers? RRM

Naw, not for DuPont for their military numbers.

AA has 2,5,7 and 9. Faster to slower. They use similar (not exact) numbers for the single base powders to match IMR numbers.


Hodgdon adds their H to the numbers. They are different burn rates though for the most part. Also generic (military) numbers for double base powders. ex. BE86, BE84 is Bullseye.

Nope.
IMR 3031 is a direct descendant of IMR 17 (1915 or so) 17 1/2 which had Tin added and was produced till about 34 or 35.
IMR 4064 is descendent of IMR 15, 15 1/2 about the same time frame.
IMR brand showed up about 1912 after DuPont lost an anti trust case.
Up until 70-71 I think, all powders sold by Hodgdon were IMR or Olin military surplus manufacture/pull down. Just different names.