MR 50 powder: Anyone have any info on it?

I recently acquired some MR 50 powder. I can't find any information on it at all. Th3e only reference to it I have been able to find is in an OLD Lyman reloading manual. I can't give you the date of the manual because the cover page with the publishing data is missing. The only two loads mentioned are on page 113: a 16 grain charge of MR 50 in a .30-06 with a Lyman 311241 bullet; and, page 120: a 16 grain charge in a 7.7 Jap with a 311413 bullet.

I have about 10#'s of the stuff and would like to use it up for practice and plinking loads for a .30-30, 7mm-08, and if suitable for a .222 or .223.

I'm making an assumption that this may be a powder manufactured prior to the Dupont IMR powders. It must have been made but there is no reference to be found anywhere on the internet.

I'd appreciate any information you could provide.

Ask over on Cast Boolits. There are a number of members over there with extensive collections of older loading manuals.

I can tell you that the 311241 was a plain based 155gr bullet and 311413 is a gas check 169gr, so we are talking about reduced loads with what seemingly is a rather fast burning powder. I have no data on MR50 but would suspect it to be a handgun/shotgun powder from the listed charge weight. Were there any velocities listed with the charges?