Any of you old timers know a modern day equal or the burn rate of Dupont 15 1/2 powder or 17 1/2 powder?
Thanks

IMR 15½ was replaced bu IMR 4064.
IMR 17½ was replaced by IMR 3031.
You probably remember that the -½ powders had tin incorporated in them.
Cheers from Darkest California,
Ross

Ross THANK YOU

I have the 1952 printing of Complete guide to handloading by Philip B.Sharpe that has loads for the old powders from WAY back. I have some Dupont pistol #5 and #6 and HiVel #3 that are still good. If they smell good and the can isn't corroded inside the old powders are still quite usable. I would be happy to relay any old powder loading info if it is in the book!