I had one of the first .375 Ruger Africans that showed up locally for a while, but after I sold it (because I didn't need two .375's and already had a Whitworth H&H) I kept a few rounds for photos and whatever.
Once in a while I try them through different actions to see how they'll feed, and so far they've worked fine through several, including an FN commercial 98 action that was converted from .30-06-sized rounds to .338 Winchester years ago. Right now I have a 7mm Remington Magnum on a 1909 Argentine action, and am gonna see if it will feed 'em as well. Suspect it will, and might even try today and report back here.
Anymore I don't think it's worth the trouble to convert a 98 action for .30-06-sized rounds to any magnum, but if one that's already been converted to feed belted rounds like the 7mm RM or .300 or .338 Winchester can be found for a decent price, it will probably feed .375 Rugers without much hassle.
It can also be used with Talley steel detachable rings (my choice) or any other good detachable if that's what somebody wants. If you prefer mounts that clamp directly to the action, a CZ 550 meant for the above cartridges would no doubt work for the .375 Ruger as well.
As for the .270 WSM, my experience is that the shorter beltless magnums work slicker in a push-feed action than any controlled-feed action. They can be made to work in a CRF action, and I owned a .270 WSM factory Model 70 Classic that fed fine, plus a South Carolina M70 .300 WSM. I also realize some people believe CRF is the only way to go, even for deer cartridges or the .17 Hornet, but having killed at least 150 deer, caribou and elk with push-feed actions, with nary a bobble when a second shot was required. (Oh, and none of those animals charged, either.) I wouldn't try to get a 98 Mauser to feed a .270 WSM, but though it just might if already designed for a belted magnum and the magazine was blocked off in the rear.
