Originally Posted by
darkker
First thing, you need to be CAREFUL with QL, it is a fun little calculator, but take it for that only. Anything made by General Dynamics is dangerously limited in knowledge, based upon weak bomb testing. Moreover Hodgdon is too stupid to know what they resell most of the time, OR based upon the fact they swap suppliers like you and I swap socks. Has QL come out with an update since last fall warning you that IMR-4064 in the 1# bottles is fine, but that the 8# jugs are now made by Rhinemetal?? Didn't think so. Most people probably still loading by grains as though there is zero lot variations out there and magically the load will forever be the same results too.... If factory brass has loose primer pockets after a single firing, then they are over-pressure. Hornady typically builds brass to 120% of operating pressure for the cartridge, whereas the revered Lapua is 130%. "Signs" happen after this. Unless the tensile strength of brass gets met, you won't see the "signs" of stretching. Watch your chronograph for signs of pressure. Are you going over book velocity? Then you already went over book pressure.