Change in IMR 4064?
Does anyone here know if there has been a significant change in the burn rate of IMR 4064 in the past few years?
I ask because I am noticing a big difference in 7mm-08 loads in my two Sierra manuals.
4th edition (50th anniversary)
Max load of IMR 4064 is 42.0 grains
Max load of IMR 4064 is 39.2 grains
That is a pretty big drop in the max load.
So what is going on here?
Did the powder change that much?
Different testing methodology?
Or is the 39.2 grain max load a "lawyer" load?
NRA Life Member
"War is an ugly thing, but not the ugliest of things; the decayed and degraded state of moral and patriotic feeling which thinks nothing worth a war, is worse. A man who has nothing which he cares more about than he does about his personal safety, is a miserable creature, who has no chance at being free, unless made and kept so by the exertions of better men than himself."
John Stuart Mill