National Forest lands are aligned with state law. If the state allows it, then it's fine. If the state disallows it, then it's disallowed on National Forest lands. The laws for National Forests are different from National Parks (allows only concealed carry if the state allows it), and National Monuments (not parks or forests). BLM lands are also different.
Cased? Just guessing I expect I must owe somebody about 2,000 years of jail time? Why would you case a gun out in the woods?