Most of the warnings are from people that advise only using rimmed rounds for better and more reliable extraction.

Same as some insist on a CRF rather than push feed bolt actions.

Of course rimmed and CRF are better choices, but not the only choices.

Ask the guys who have actually owned them, and see what they say. I haven't owned rimless chamberings, except for my .30-06 and not enough experience with that yet. But do rely on the comments of members on here, and usually claim no real problems.

However almost all the reputable gunmakers have been offering magnum and rimless rounds like the .375, .416 and .458 Win Mag in doubles for several decades, and wouldn't if there were a lot of problems.

Up to the buyer of course.

I hope some of members pipe up and give their direct experience and knowledge.

PS Before posting, had a look at the Verney-Carron PDF brochure I had open. Interestingly almost all the chambering they list ARE rimmed. Good to see. It mentions a .375 HH, which might be rimmed or the magnum chambering?

One chambering of interest is the .30 Blaser R, which would be close to the .300 H&H Mag or Rimmed chambering.

If you want a .30 calibre, the .30 Blaser R might be worth looking at too.