TScottO,
Everything that "akpls" has said is true. I own three Ruger M77 Magnums, a .375 H&H, a .416 Rigby and a .450 Rigby that I built. I don't know why Ruger didn't bring out the .450 Rigby instead of the .458 Lott. They went against the grain when they decided to chamber the .416 Rigby over the .416 Remington. Now the .416 Rigby is a big seller for them. The .450 Rigby beats the .458 Lott and does it with way less pressure, about 15,000 lbs. less pressure. Same with the .416 Rigby over the .416 Remington. Personally I would like to see Ruger bring out the 1, 2, 3 Rigby punch by bringing out the .350, .416 and the .450 Rigby's.
akpls,
My M70 .450 Marlin I got from Clark also but I went with the in the white barreled action due to having to restock the rifle due to my size(6' 7 1/2", 273 lbs.) factory stocks don't fit. I had my gunsmith install Express Multi-Leaf rear and hooded ramp front sights along with a barrel sling stud. I mounted a Burris 1.75-5x on Leupold QD rings and I used this to take Caribou, Moose and Black Bear with one shot each last year in Alaska. My brother in-law used it to take his Brown Bear but used three shots(the last was a insurance shot). It's a great cartridge when loaded right. Lawdog