In Wyoming you can open carry just about anything. Long arms included. You don't need a permit to concealed carry, either.
There is no limit on the varieties of knives which may be owned in the state of Wyoming, and which may be bought, sold, given or received as gifts, manufactured, and so on. All kinds of folding and fixed knives, single-edged and double-edged blades (such as hunting knives, Bowie knives, daggers, and stilettos), switchblades, gravity knives, balisong knives, swords, machetes, push knives, and disguised blades such as lipstick knives are legal to own in Wyoming.
Any Wyoming resident can conceal carry any dangerous weapon, including knives, provided that they meet the concealed carry permit requirements. These include having been a Wyoming resident for at least 6 months, plus a resident of the United States; being 21 years old or older; has not abused controlled substances within the past year; does not have a misdemeanor conviction in the past year, or a felony conviction ever; is not legally incompetent; and has not been involuntarily committed to a mental hospital.