Other than no CCW/CHL the WI laws do not appear to be all that strict. They have their own background check, with $8 fee, for hand guns, but long guns appear to have few or no controls beyond the federal ones. It is a hunting state after all.
They also have a "strong" RKBA provision in the state constitution.
The people have the right to keep and bear arms for security, defense, hunting, recreation or any other lawful purpose. WISC. CONST. art. 1, § 25
Tons of guns here in Wisconsin... Mostly long guns as you stated at least up North here, but plenty of arms and ammo nonetheless. As for handguns, we SHOULD have CCW permits and IIRC we’ve been trying to get that changed for a few years now... Not helpful having a Democrat for a governor though. He’ll raise our taxes till the cows come home, but doesn’t want people to be able to defend themselves... go figure...