How bad did I screw up?

[Widetracker]

308 is not a legal deer round in Indiana. Case lengths are capped at 1.8 inchs and bullets must be at least .357 in diameter.

 

[Mgderf]

308 is not a legal deer round in Indiana. Case lengths are capped at 1.8 inchs and bullets must be at least .357 in diameter.

You are correct, almost.

The specs you quoted are indeed the regulations, for rifles.
Pistols can use down to a .243cal, with no length limits.