SR 7625 was the dupont nomenclature....stood for shotgun/rifle. after they ceased production, it was made and marketed by imr - who marked their production as sr 7625 - but for the purpose of distinction many call the later powder imr, to separate the two different eras of production.

as far as i know, there is no difference in composition between the two.

best regards,

tom

"it's a poor sort of memory that only works backwards."
lewis carroll, Alice in Wonderland