I did fiddle around with it some. My grinder has two different metal plates for controlling the size for the chunks of meat that come out the end. The plate with little sized holes, which I tried first, has numerous holes and each just big enough for a whole barley grains to pass through, while the plate with larger holes has about 6 or so holes and could have whole corn kernels pass through it.
When using the plate with little holes, I got flour and some blisters! It was extremly difficult to move any amount of grain through the grinder on that setting. With the large holed plate, a lot of grain just falls through it, but when you keep the grinder and hopper jam packed the success improves a little, giving some crunch without having to break your arm grinding the whole shabang into dust.
It would be neat to find out if there's something on the market that could convert the meat grinder into a grain mill. Seems like with all removable/replaceable parts that would have been common practice 100 years ago. That is, assuming that was a time before people would be concerned about raw meat ending up in their flour.