Hey Larry, I have a Weaver C-4 on my 521-T.
It originally had Lyman peeps when Dad bought it, and those are what I learned to shoot with, but one day Mom came home with an as new in box C-4, complete with the paperwork, that she had found at a yard sale for $1!
Dad agreed that I could scope it, so I freighted the bill to have mounts installed.
Very nice little scope, and made it even deadlier on squirrels and even greater distances.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.