The shooting happened at 12:45 p.m. Wednesday outside Sullivan's Tavern on South Pennsville Auburn Road.
Police say the victim has been identified as 19-year-old Cecil Bond IV of Middletown, Delaware.
According to investigators Bond and an accomplice, 22-year-old Matthew Beckford of Newark, Delaware, travelled to Carneys Point to illegally buy prescription medication.
The alleged sellers of that medication were 49-year-old James Trotman of Warwick, Maryland and 40-year-old Charles Foster of Eastampton, New Jersey.
The four met and, police say, Bond and Beckford tried to rob the other men at gunpoint.
There was a struggle and then, police say, Trotman shot Bond in the head.
Bond was taken to the hospital where he later died.
Trotman was charged with murder, and Foster was charged with drug-related offenses.
Beckford was charged with robbery and possession of a firearm.