 Many subsequent cartridges of "magnum" nomenclature were based on the original .375 H&H cartridge, so over time the belt became something of a standardized attribute, expected as part of a "magnum" cartridge.Many cartridge designs of the last century include this belt, but do not really require it.In the last decade or so, there has been a trend toward beltless magnums, virtually all of which are heavily shouldered designs that obviate the original motivation for a belt.