While not a Rewa ,took my 585 Hubel Express on a Ruger No1 to Arnhem land and got two buffalo with it ,with load of a 750 gr Bertram softpoint and 150gr Ar2213sc which gets 2000 fps ,the Hubel Express can be loaded to about 2600fps[and exceed 600 NE energy levels] but 2000 is enough for me and did the job on two buffalo knocking the snot out of them ,i also took a 458 Lott and 378 Weatherby ,the 585 had a more definite effect on buffalo ,on one animal the bullet entered the shoulder and exited near the pelvis which we worked out at four feet of penetration with a softpoint, in future if i go again i would only take the 585 .Wal Winfer had some Fraser side lever 577 Rewa[s] for sale some time ago .