I have the following code from recording a macro:

Windows("2nd 05-01-13 MB.xlsx").Activate
        Sheets("Master").Select
        Sheets("Master").Copy After:=Workbooks("1st 05-01-13 MB.xlsx"). _
        Sheets(5)
I am running the macro in open file "1st 05-01-13 MB.xlsx"
I want to go to file "2nd 05-01-13 MB.xlsx", copy the worksheet "Master" and insert it after the last worksheet in file "1st 05-01-13 MB.xlsx"

The file names will always begin with "1st" and "2nd" but the date and letters may change.
I would like to 'clean up ' the code so that it will pick up the correct file names regardless of the change in date and letters after the "1st " and "2nd ".

Any help would be appreciated.