I really liked @brettdj's code, but then I found that when I added additional code to edit the copy, it overwrote my original sheet instead. I've tweaked his answer so that further code pointed at ws1
will affect the new sheet rather than the original.
Sub Test()
Dim ws1 as Worksheet
ThisWorkbook.Worksheets("Master").Copy
Set ws1 = ThisWorkbook.Worksheets("Master (2)")
End Sub