1930 british penny striking error?

Welcome to numista.

You have, in my opinion, a PMD (Post Mint Damage) coin.

Thank-you for your response,I have wondered this ,the tarnishing and wear seem to match  the coin and the impression,which  would indicate the inprint to have occurred very shortly after minting.It looks like a 5 ,the size used for say a 50 cent Australian  coin, being 1930 british mint there is no coin that I am aware of the had a 5 that size and was being minted in 1930 which could have coursed this ,are you aware of any?

It’s post mint damage 

Rodger that,thank you ,what where they thinking,hell do you guys remember putting the pennies on the railway tracks,fastened with a bit of copper wire.now that is what I call post mint damage.