You will need to check with the Cass County Planning Commission for Zoning regulations. You might need to get a Conditional Use Permit to do this if you have any non-family members shooting there. In the past there was a thread on here where someone in Cass County got in trouble over this, but I can't remember exactly when (2 years ago?).
Excerpt from the Planning Guide:
CASS COUNTY ZONING REGULATIONS REPRINT JANUARY 2015
52
8. Commercial recreational and camping areas including fishing, hunting, gun clubs,
rifle range, trap shoot, and similar uses