We can't get deer to eat the protein. They might once in a blue moon but that's it.
Mix it 50/50 corn and protein until they start hitting the feeders regularly. Then go to 25/75 corn/protein the next filling. Then go 100% protein and you should be good.
But if you have good forbes and browse, they will eat that before they eat protein. That's why it's called supplemental feed and not a full-ration.
I just returned from our place in NE Webb Co. The deer are still eating a little protein, but not heavy. We're not going to refill until later in the season once this load is gone. Pending habitat/deer condition. Bucks look outstanding this season. Got two nice rains down there Saturday and Sunday on our place. The Callaghan looks to have gotten quite a bit more, but we'll take it. Most of our tanks are full to 75% full. Habitat is the best it's been in I dunno when.