Uh, Calvin? When they went from 2.75 & 3" Magnum to 3 1/2" magnum, they also did a number on the pressures. I had a few hundred 3" Magnum shells that had been baking in the hot summer attic for about 50 years ... these were the old Remington Nitro-Express shels. Apparently the nitro would semi-liquify in the heat, leach its way into a form that would detonate rather than conflagrate. I never chased them over a chrony, but I knew a half-dozen of the things would pound the livin' snot outa me, give me a "Nitro" headache and defoliate a Canadian Honker farther than anything else I ever shot. I do believe there are a few boxes of those brutes still around in the attic, still baking in the heat every summer, lying in wait to bust another stock against the shoulder of another innocent child who wishes he could hunt elephants or other monsters of his dreams.