That depends on your local laws - call a gun dealer and ask - they'll be happy to discuss the issue with you.
NICS takes a couple of minutes.
Yes. As long as your charge was a misdemeanor and not a felony. You may have a delay in your ability to actually take the gun home if the background checkers decide so. But eventually you should get the gun.
You have to be 18 to buy a long gun and 21 to buy a hand gun.
For a long gun you have to be 18. For a handgun you have to be 18.
18 for a long gun, 21 for a handgun.
18.
18 for long gun, 21 for hand gun
Legally, you can't own a gun until you are 18 (long gun) or 21 (hand gun).
Federal law says you must be 18 to buy a long gun
Some period of time
If you tried to buy a gun and it came back as a "delay" that doesn't have anything to do with the State of Kentucky. Background checks are processed through the federal system, and what a delay usually means is that there is something on your record that they cannot verify, or there is someone with a similar name to yours and they are trying to verify your identity.
There are a couple of options. You can go into a gun shop and buy one. You can buy one from an individual, as long as the gun isn't stolen. You can order one over the internet and have it sent to a gunshop near you. In TN, you must be 18 to buy a shotgun or rifle, and 21 to buy a handgun.