Weird problem with front drum brakes

The weird thing is We drove the car last week and had no issues. Yes the drum spins without the wheel on , we put the wheel on and tighten the lugs nuts it locks up and will not spin ? This is why I'm asking the question. It's not obvious what the problem is?? I have worked on these cars since I was 12 (I'm 60) I've never seen this before. I have never been a fan of front drum brakes but we're just trying to make sure they're working until we do a disc conversion next winter.