Lee Enfield 303 British, assembled out of spare parts by my neighbor at the time who was a fair to middling basement gunsmith. I was young and poor and really didn't know a lot about big game guns, and it was free, so I did not even think twice. I put a $49.99 Bushnell scope on it (I think the thing even had plastic lenses instead of glass), and off hunting I went. Lots and lots of hunting, LOL. Eventually I got the rifle bug and have been through a bunch of guns since then, but I hunted with that thing for many years.
Until fairly recently, my wife and I had killed more big game animals with a 303 Brit, looking through a 49 dollar scope, then all of the nice rifles we've owned since then combined. Dozens of deer, several elk, a couple of bears, etc. My wife even knocked over a mule deer from approx 300 yards out with a 180 Winchester Power Point.
All the things you would think would make a rifle inaccurate were wrong with it; wood stock touching the barrel, crown look like it had been beat with a ball peen hammer, horrifically bad scope mounting system, headspace was so bad that later when I started reloading I could only get two firings before case head separation, the parkerizing was long since mostly worn off, and the gun look like it had been run over by a truck several times and then left in the woods over a winter or two. But it was a solid 1.25 MOA gun with Winchester Power Points, and a 3/4 MOA gun with handloads.