Its a regional dialect common to the South. When I was in the service, I met guys from all over. Some from New York or Jersey would say 'youse guys'. A fellow from a rural area up in Illinois would say 'you uns'. They all meant the same thing as y'all (short for 'you all'). If you're in Louisiana its just 'vous' and if someone says, 'allons dance'...... Get up and dance!
Best regards,
Harry
P.S. >>> If you want some real good barbeque brisket or chicken fried steak or bowl of chili...... Come to Texas.