The only place in the General Statutes I can find a specific mention of "blackjack" is in
http://www.ncga.state.nc.us/enactedlegislation/statutes/html/bysection/chapter_14/gs_14-269.2.html , where it says
"(d) It shall be a Class 1 misdemeanor for any person to possess or carry, whether openly or concealed, any BB gun, stun gun, air rifle, air pistol, bowie knife, dirk, dagger, slungshot, leaded cane, switchblade knife, blackjack, metallic knuckles, razors and razor blades (except solely for personal shaving), firework, or any sharp?pointed or edged instrument except instructional supplies, unaltered nail files and clips and tools used solely for preparation of food, instruction, and maintenance, on educational property.
(e) It shall be a Class 1 misdemeanor for any person to cause, encourage, or aid a minor who is less than 18 years old to possess or carry, whether openly or concealed, any BB gun, stun gun, air rifle, air pistol, bowie knife, dirk, dagger, slungshot, leaded cane, switchblade knife, blackjack, metallic knuckles, razors and razor blades (except solely for personal shaving), firework, or any sharp?pointed or edged instrument except instructional supplies, unaltered nail files and clips and tools used solely for preparation of food, instruction, and maintenance, on educational property."
However, 14-269 specifically prohibits
http://www.ncga.state.nc.us/enactedlegislation/statutes/html/bysection/chapter_14/gs_14-269.html
"SUBCHAPTER IX. OFFENSES AGAINST THE PUBLIC PEACE.
Article 35.
Offenses Against the Public Peace.
§ 14?269. Carrying concealed weapons.
(a) It shall be unlawful for any person willfully and intentionally to carry concealed about his person any bowie knife, dirk, dagger, slung shot, loaded cane, metallic knuckles, razor, shurikin, stun gun, or other deadly weapon of like kind, except when the person is on the person's own premises. "
I think that's where you'd get crossways of the law. NC has a lot of old stuff on the books- heck, far as I know, ALL the old laws are still on the books, all the way back to Sir Walter Raleigh. It's a complicated state to go about armed in, in many ways. Anything that can be construed as illegal very well might in certain circumstances.
It's too easy in NC to carry useful things that are definitely NOT illegal, to risk getting caught up in a potentially troublesome situation over something someone else views as sketchy. A plain wooden crook-top cane or a walking stick is too commonplace to cause issues, and won't get a second glance. Note, however, that 'loaded canes' ARE specifically included in the list of prohibited items. I carried my blackthorn on campus Saturday to a function I had to attend, and didn't get a second look.
fwiw, ianal,
lpl