One thing I learned about full-auto in the few times I've dabbled is that you might as well sign your paycheck over to Cheaper Than Dirt. We had a landowner allow an MP-5 course to be held on his land for free one time "as long as you leave the brass." He got a whole lot of brass...
Set yourself up with a Dillon. I keep hoping my wife, inlaws, or parents will come through for me and get me a nice little 550B. They've even got an automatic case feed for the 550 now. Heavy shooters can make up their costs pretty quickly compared to buying off the shelf.
Were it not for NFA'34 and other such legislation, I might enjoy having a full-auto .22LR. Not sure anyone even makes such a thing, though.