If you just need to do some zeroing, you can try A&A Shooting Range near Nelson Ledges.
The last time I went there (in the '90s), it was VERY rudimentary, basically just a muddy field, other than the shotgun ranges. It reminded me of Knob Creek during the '80s, before the machine gun shoots started getting big.
You'll probably have to bring all your own target gear, including stands/frames.
Your other option is Kelbly's down near Orrville. It's been so long since I was down there, I don't know what your options are as a non-member. It's where the SERIOUS benchrest shooters go.