Figure in you cattle transportation costs, shrink when you sell, sickness pulls, death loss, feeding expense, calf market volatility, and if it was a winner, everyone would be doing it.  But you might just have an ace up your sleeve nobody else has.  Unless you really enjoy the cattle business and working with them and don't mind the potential you may make it big on this venture or may loose your shorts, you may be better off just selling the hay and enjoying your winter on the golf course.

On 2nd thought, if you really like to play it big, you could buy the calves and feed all your hay through them and then send them off to a yard and retain ownership on them through slaughter, or when the hay runs out if you can't find someone to give you what you want for them, then retain them.  Lots of options, but you better like cattle if you are going to mess with them, as there is good money to be made and lots of money to be lost.  If those calves haven't been taken care of before shipping and you're a novice to recieving calves, they can start dropping like flys a week after they hit your lots.