Lol that escalated quickly.
"I don't recommend it. It would be quite illegal. You could be fined £1000. Don't shoot people with sawn-offs"
But yeah you're right, unless you're loaded up with skull breakers (self-defense paintball ammunition which i'm 99% sure is illegal here) you'd be better off whacking them with whatever you have to hand.
Can you tell that I've heard it all before?
Covered every argument other than the bravado one.
And you're right on the skull breakers - illegal here, as are all the other 'less than lethals' - pepperball etc
Anything that is a 'self defence weapon' is illegal in the uk, you have the right to defend yourself, property, family and even random strangers that you find being attacked in the street (if they are in real danger - not the right to join a fight)
Pre-meditation is not allowed, but you can do anything that is later considered reasonable for the state of fear you were in at the time, and use anything that happened to be to hand without the need of hindsight.
Contrary to the daily mails opinion what is reasonable cannot be absolutely defined - what's reasonable can vary according to circumstances, eg the blackmailer convicted of murder on 'the reasonable man' but then reduced to manslaughter on appeal based on 'the reasonable 15 year old' and the circumstances . Camplin vs dpp, one of the more memorable pieces from my legal education