RE: Cracked corn for a spinning feeder ?
We have a feed store that sells whole corn and soybeans mixed. Has worked fine in many feeders (spin type by HCR mostly) for years.
For turkey and especially if there are deer around I always mixed in 2 bags of milo with the whole corn. The deer eat the corn early and the milo is still there for the turkeys when they get there. OR the turkeys clean up some of it but there is usually a bit of milo left for the deer to nibble on.
FWIW straight whole corn poses no problems for turkeys though.
As to mixing stuff in, we'd add hog wild to the feeders every now and then to attract the hogs at times. Never clogged one of ours. YMMV.
DO be careful on pellet type feeds. I've had some clog up, some get damp and clog up, some not feed, some just work all the time. Sometimes the jams have to do with how close the spinner plate is to the funnel end. You may have to adjust that.
Jeff