Any chance your drill is on reverse (if you are using one)?
haha, I wish that was the case.
When adjusting the gap with a feeler gauge, do you tighten it down as far as you can go and still be able to pull the feeler gauge out?
I used to get efficiencies in the mid 80s with my LHBS mill and haven't been able to dial mine in yet. I've been getting 50-55% with my new mill. I had what I thought was a great crush this weekend, but ended up with 56% efficiency. At one point I thought my crush was too fine.