Shooter McGavin -- Takes Unhappy DWI Mug Shot

10:46 AM PT -- McDonald was released at 7:20 AM ET. He has a court date on Dec. 11.

9:30 AM PT -- Shooter was SUPER wasted ... and barely able to utter a coherent sentence ... this according to one of the guys who shared a beer with McDonald just hours before his DUI arrest.

Jonathan Mincher tells TMZ he and his buddies (seen in the pic below) were drinking at Lagerheads Tavern in Wrightsville Beach, NC when Shooter walked in with a friend.

Mincher says Shooter was drinking beer ... and could hardly speak. But we're told he was a sport ... and bought Mincher and his crew a round. Mincher says when he left the bar at 1 AM ... Shooter was still there going strong.

Christopher McDonald, who played Shooter McGavin in "Happy Gilmore," was busted early this morning for DWI.

The 58-year-old actor -- who also played Travis Cole in "Dirty Work" -- was popped by North Carolina Highway Patrol deputies in Wilmington ... cuffed and taken to jail at around 4:30 AM.

Law enforcement tell us ... Shooter's blood alcohol level was .15 -- almost double the legal limit.

Before the arrest, Shooter was drinking beers with a few guys at a bar -- and definitely appears toasty.

It appears he was in Wilmington filming a movie called "The Squeeze."

Movie bigwigs will have to post $1,000 to get their star out of the slammer.