I've finally started reloading my 416 Ruger using Shooters World seriously previously I've only had time for a few loadings.
A member on here was kind enough to send me a variety of cast under 400gr so I could narrow down a mold.
There is not a bunch of data out there for reduced loads using lighter cast but I ran across a comment that the Ruger is close enough to a 416 Rem Mag except the neck that starting loads for it could use bottom end Rem Mag loads minus 5grs.
This sound reasonable? I tried a few 290gr cast with this method. 5gr under starting 300gr Rem Mag minus another 10% for safety. Brass looked fine, no leading and a little unburnt powder. Recoil... well its still a .416 but certainly well shy of the 400gr solid buffalo stompers.