In reply to Jon Stewart:
> Bear in mind also that the firing times are a bit of a paper exercise - they do whatever they want on the day, after all, what's you or anyone else going to do about it.
I strongly challenge that statement. Range timings are stringently adhered to, be it small arms, tanks, artillery, whatever. Not only is a good husbandry, but on a range like Castlemartin there are all sorts of external assets to co-ordinate (radar operators, safety craft at sea, air space restrictions, equipment support people) which are either time-critical themselves or rely on contractors who rigidly enforce their hours. Having run small arms and vehicle ranges of various type, I would not like to be the one firing outside of published hours.
As said previously, it can be the case that firing is published but doesn't happen. Usually this will be because a slip day is factored into a progressive firing schedule, and if all goes well (no equipment failures, good shooting, good weather) then the planned exercises will finish early and the range can be opened.