I don't know if this will help. But if you can get this in front of someone, then ask them what statute restricts someone between 18 and 21 from possessing a handgun?
14‑269.7. Prohibitions on handguns for minors.
(a) Any minor who possesses or carries a handgun is guilty of a Class 2 misdemeanor.
(b) This section does not apply:
(1) To officers and enlisted personnel of the armed forces of the United States when in discharge of their official duties or acting under orders requiring them to carry handguns.
(2) To a minor who possesses a handgun for educational or recreational purposes while the minor is supervised by an adult who is present.
(3) To an emancipated minor who possesses such handgun inside his or her residence.
(4) To a minor who possesses a handgun while hunting or trapping outside the limits of an incorporated municipality if he has on his person written permission from a parent, guardian, or other person standing in loco parentis.
(c) The following definitions apply in this section:
(1) Handgun. – A firearm that has a short stock and is designed to be fired by the use of a single hand, or any combination of parts from which such a firearm can be assembled.
(2) Minor. – Any person under 18 years of age.
BTW, there is no statute that allows OC. And there is no statute that I am aware of that allows 18 yo's to carry. What happens is, minors are prohibited. So that covers those under 18. The law is silent on those from 18-21. Which technically means you can, since that which is not forbidden is allowed. But LE tends to not think like that. Then you have the issue of FFL's not being able to sell handguns to those under 21. And everyone just assumes anyone under 21 can't buy a handgun. Which is inaccurate. And you find yourself in one of the most vague areas of gun law in NC. Good luck with it.
I could careless about a chp can't conceal until I'm 21 but I can take the class. There's also nothing saying you can't own a handgun and carry under 21 it just says under 21 you can buy from a ffl dealer. Many ppl under 21 have got a ppp.