The two rounds are extremely good ones…but they are at their best with heavy bullets.
I have made a lot of 6,5x57 rifles and I own a kipplauf chambered for the 6,5x57R.
A 140 grainer work better than a light bullet and I very like the RWS DK load that, on use, don't differ greatly from my beloved 6,5 Creedmoor.
The 6,5x57 (R) as a good reputation as an "Alpine" cartridge, I want to say a typical Chamois load. My son has built for his own use a 6,5x57 Mauser that now count more than an hundred heads of various mountain games and he think that it's on par with the .270 Winch.
The 7x57 (.275 Rigby) is a perfectly "balanced" cartridge and I use a Rigby for driven hunt. My choice goes to the RWS ID "Classic" (Brenneke TIG) 162 grains that is perfect for all our European games, from roe deer to red deer and wild boar.
I don't know very well and I haven't ever used the R version, but two goods friends of mine rely on it for all games (including mountain games) as they use light Merkel drillings chambered for that cartridge.
For me, and me alone (!), the 6,5 is more mountain oriented and the 7mm is more an all around cartridge…but that's only my opinion.

DORLEAC
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