Copy and Paste Loop in Cells Only

I would like to use VBA to automate the copying of one cell to the one below, on a loop. For example, cell A1 will contain text that I want to copy and paste into cell A2, then copy cell A2 and paste it into cell A3 and so on right through to line 3000 in column A. There will be different text in cells A6, A12, A18 which is why I can't just do a full column copy or drag the cells down. So cells A1-A5 will contain the same text, cells A6 to A11 different text and so on for every 6 cell increment. I'm rubbish with VBA so have no idea how to do this :-( Any help would be much appreciated.

You are a genius! Thanks so much, that's worked perfectly :-)

Can I match the font down the whole column automatically?