Earl Grey's competition medal

Hi does anyone have any idea about what this medal was issued for and if possible when and how many there are.

Earl Grey's competition medal, Diameter 51mm, 3mm thick, 54.1 grams. Obverse: George killing a Dragon in the style of Benedetto Pistrucci scroll below with motto Quo Vocant Fata. Reverse: Lettering only Earl Grey's Competition Medal. Plain edge.

Quo Vocant Fata "Wither the fates call." Motto of the Royal Northumberland Fusiliers

Image can be viewed by clicking the link below.

Thanks Dave.

http://en.wikipedia.org/wiki/Albert_Grey,_4th_Earl_Grey

Not entirely what it was for...but I believe this is on the right track.