What is the maximum safe operating pressure of the Handi Rifle? I notice from that chart that some of the available calibers have higher pressures than some of the magnum calibers that I thought were not possible in the handi. For instance it shows the 270 at 65,000 and the 25-06 at 63,000, but the 7mm rem mag at 61,000 and the 375 H&H mag at 62,000. I'm confused!!!