I just got back from Argentina.  I can't tell you how pleased I am with my Christensen Arms 300 Ultra Mag.  I took a Red Stag, Fallow Deer, Axis Deer, and a Patagonia Ram.  I guess what's so impressive is...

 

...for a 300 Ultra Mag there is so little recoil.  The gun only weighs 7lbs and with a Swarovski 3x12 scope while using Barnes 180 Triple Shock each of the animals were harvested with clean, one shot kills.

I'll be taking my Christensen Arms 338 Ultra Mag to Africa in August and I have no doubt it will perform just as good. 

Four, one shot kills.  That's what I call "Whack-n-Stack".