FOR A FEW BRIEF YEARS, RUGER BUILT RIFLES with honest-to-goodness magnum-sized, Mauser-type actions. Colloquially known as RSMs—for Ruger Safari Magnum—these rifles were chambered in hard-hitting cartridges, including .458 Lott, .416 Rigby, and .375 H&H.
The Lott and H&H cartridges are proper magnum-length magnums but have standard 0.532-inch belted-magnum cartridge heads like the .300 Win. Mag. and 7mm Rem. Mag. The .416 Rigby, however, is bigger around. Its case-head diameter is 0.590 inch, and a .416 Rigby cartridge is bigger in diameter at the shoulder than a .458 Lott is at the belt. Few actions are suitable for the .416 Rigby, but Ruger’s Model 77 Mark II Magnum was. As such, it was the only classically configured, American-made rifle chambered in the cartridge.
Mechanicals
Thanks to Bill Ruger’s perceptiveness, the RSMs…
