When the battle began the ships were said to be about a 1000 yards apart

That was the critical bit I was missing.

The holes didn't appear to be the sort of damage from shrapnel but appeared to be neatly round and about the same size as from a standard machinegun. I can't recall the calibre(s) of such weapons in the German armory but British .303 (the smallest of such weapons) machine guns would have had open sights calibrated to at least 1000 yards. I couldn't see the locations of the damaged boats (whether they were still attached to the main hull or not) and was aware that naval traditions on all sides were (generally) more "gentlemanly" than allowing lifeboats to be shot at. But it was a question that arose.

Thanks.

Cheers, Rowan