Several companies make steel Weaver style bases. Leupold, Weaver, Warne, and probably some others. Availability depends on the particular rifle. You can also get Picatinny style one piece bases. They give you ring location choices, but they tend to be tallish bases. I think they look a bit out of place on hunting rifles, especially "classic" rifles.
EDIT: I somehow missed the few posts above that discuss "who makes what."
As far as square/round, I too have seen Weaver brand bases AND rings with both, and I also believe date of manufacture is the reason.
As long as the rings fit on the base, which isn't always the case with Picatinny rings, unless it is a massive scope on a really hard kicking gun, I don't worry about it. Unless things are matched very carefully, you likely have only point or line contact at that interface anyway. You have a better chance with square slots and cross pins, but even then they have to be "dead nuts" square with each other.
To digress a bit (but hey, I started the thread), does anyone know how Warne bases and rings are made? I thought the rings might be "other than machined", but I believe they say the bases are machined.
Best,
Gun Doc
Last edited by GunDoc7; 08/15/18.
