bstomper
Well-Known Member
I am doing load development for my Winchester model 70 7mm RM. I am using Hornady brass, H1000 Federal 215m primers and 175gn Accubond LR bullets. Initial COAL is 3.360". I shot yesterday in -4c temps. The Nosler data says 65.5gns is max for the 175's and Hogdon and barnes say 64.5gns max at a COAL of 3.290". I am at 70.0gns and have no signs of pressure yet. No sticky bolt, no cratering on the primers but I can begin to see just a slight flattening of the primers. I am sitting around 2920 for speeds. I have a great accuracy node that is worth exploring at 68.2-2894fps, 68.4-2899fps and 68.6-2889. It confuses me a bit that I am 5gns above the stated max charge and not seeing pressure. Is this common? I could understand maybe a couple grains because of the longer COAL but 5 seems like a lot. I'm not to sure if I should continue to go up in charge weight until I see definate pressure signs and back down from there or just continue with the node at the 2890fps. Any help would be appreciated.