Cardeer..looks like a nice sheep hybrid,I'd say a good Corsican ram. Which is usually a cross between a Mouflon and a Barbado. But as big as the mass is on those I'd say there was some Argali or Big Horn in the history somewhere.More than likely Argali they brought some into Texas years back, and crossed them with every thing. But being dark color like that there is definitly Mouflon or Barbado in it some where though.
Hope this helps.