If you are careful you can make your brass last a long time. Maybe 10 or more loads? So brass is 1/10th the cost of piece of brass.
Roundball, figure reloading cost is 1/2 cost of factory ammo. There are a LOT of variables though that can change that..
But, if you figure in the cost of your reloading equipment, the cost goes up quite a bit. THAT all depends on how much you reload, how much you spend on reloading equipment etc.
Tell the wife it's 1/2 the cost!
Truth is stranger than fiction, fiction has to be believable.