Ian ,
Horse artillery- uniforms followed the cavalry in style : blue with red facings and yellow buttons. The blue shako had brass crossed cannon barrels under the cockade at the front , with red top band , red pompom , side chevrons and cords. A drooping red plume was worn. The blue double -breasted tunic had red piping to the blue collar and cuffs , to the lapels and bottom0f the tunic, and red epaulettes were worn. There were blue grenades on the red turnbacks. Breeches were blue with twin , wide red side stripes and black leather booting up the insides of the legs. Belts were white and brass hilted , light cavalry sabres in steel sheaths were carried. The black cartouche bore brass crossed cannon barrels under a flaming grenade.
Foot artillery- wore the same colours , but with dark blue infantry trousers with twin red stripes over white gaiters
Guard artillery [foot] - wore busby with red bag and cords and white over red plume , blue dolmans and breeches, red braid and pointed cuffs . Three rows of yeollow buttons, blue trousers with red side stripes.
Guard artillery[horse] - the same as the foot artillery , with the difference they had five rows of buttons and light cavalry equipment with blue sabtretache , edged red with a yellow eagle, also there was black leather booting up the inside of the breeches and all belts were white.
source--Kiley K F and Smith D 'Military uniforms of the 19th Century' pp 52-3
hope this helps
regards, Ian