I was playing around and hunting and I found this and it works 100%
Requirements: Firefox web browser , INTERNET
1) Go to https://addons.mozilla.org/en-US/firefox/addon/flash-game-maximizer/
2) Click continue to download..
3) Click accept and install..
4) Let it download a dialog box will pop choose install..
5) A restart box will pop down click restart Firefox..
6) Load up battle pirates and click the loading screen and press F12 on the keyboard.
7) Enjoy full screen comms!!!