Actually, I recently pitted the .44 Mag against the .45 Colt in a penetration contest using factory loads from Grizzly Cartridge -- the 300 grain WFN against their 300 .45 Colt LFN load. The .45 handily out penetrated the .44 despite the "advantage" of a greater sectional desity. Plus, the .45 has a decided edge in the pressure department and develops 20% less than that .44 Mag load. While this is not conclusive, it seems to happen more often than not.