Found what I was looking for in a old american Rifleman test done in june 2000.They compared all the .458 size rounds with the 450marlin hornady bullet 350Gr.Flat point design loaded in the 45-70,450marlin,458wm.They shot em in water jugs and the 450 went thru 6,the 45-70 went thru5 & the 458wm 4 .The 458wm was going so fast for the bullet design it just blew it up.Looks like they all flew really flat out to about 150 yards.The article said the 450 marlin was designed after the.458x2American wildcat by frank c. barnes,and the450 alaskan byHarold Johnson,The ballistics of the 450 marlin fall between the 45-70 and the 458win.mag.Pressure is in the mid-40,000p.s.i. range.