Automatic 24 Hour time format

Hello Excellers,

What is the VBA code to convert a cell into 24-Hour time format that I could add to the sheet's code?

0800 becomes 08:00
1500 becomes 15:00
1815 becomes 18:15
Etc...

This is what I am looking for that is similar to the code below that converts the letters to all Uppercase:

Formula:

Private Sub Worksheet_Change(ByVal Target As Excel.Range)

If Target.Column > 8 Then Exit Sub

On Error GoTo ErrHandler

Application.EnableEvents = False

Target.Formula = UCase(Target.Formula)

ErrHandler:

Application.EnableEvents = True

End Sub

Thanks!