Loop through Array then Offset Range by given Value

How do I use a loop to offset a range on each looped Array?
This is what I have:

Formula:

Dim linerng(1 to 30) as Integer, i As Variant



For Each i In linerng

    Set linerng(i) = Worksheets("Roster").Range("A5:AD5")

But then I need to offset A5:AD5 by a row value of 4 each time it completes a loop. Any ideas ?