I'm too lazy to be a hunter so I can't really call mine a big game rifle, but I do have a left-handed .460 Weatherby with Lazermark stock that I like to take to the plinking range once in a while.
My target of choice is a one-gallon can of hominy corn at about 20 yards.
Interestingly, the gun which I bought NIB in 1994 via Shotgun News came with a 100yd test target with a three shot group that measured 1.3". After firing a few shots from the bench to zero the scope, I shot a 100yd group of 1.7" with virtually identical relative shot placement.
Like many others posting here, I also have a nice 1895 Marlin in .45-70. I was at a gun show in OKC (also in 1994) and happened to run into my oldest nephew. We cruised the aisles for a bit together until we came to one of my favorite dealers at the time. I spotted the Marlin on the table and quietly said to my nephew, "I can probably get that for $250."
The dealer came over and I asked him what he had the Marlin priced at and he said, "$250." I told my nephew, "Dang, he called my bluff!" and paid the man.