I have an image of a bombard on the march, alongside Swiss troops, taken from the Tschachtlan edition of the Bern illustrated chronicle of circa 1470 - shown here. When the Perrys released their wagon packs recently, the opportunity arose to try and re-create one of these for my Burgundian army. This is a WIP posting about the model.
It appears that non-wheeled larger artillery pieces were loaded onto large carts for transportation. The wooden frames that the barrels rested on were either broken down into parts or even rebuilt completely as circumstances required at the point of use. I'm using the open sided wagon and swopping horses for oxen, as the bombard barrel is relatively large and was therefore likely to have needed the extra pulling power of two pairs of oxen (plus I like the models!). According to Smith and DeVries book on the Burgundian artillery, a gross bombard barrel recorded in 1445 at Namur for instance, weighed 8,200 livres (which I estimate at about 4,000 kilograms).
The work in progress picture shows the oxen attached to the base; I've used a small chain to link the two pairs of yokes. The wagon itself will have to be attached last, when all the basework is fully completed. The bombard is a Foundry one, to which I've added small wedges of wood for the transportation. The box and barrel will also be loaded on to the wagon. I'm aiming to reproduce the wooden cover by cutting down and adapting a Kingmaker Hussite wagon side I have left over. The Perry drover will be added, as will one of the labourers currently on the 'greens workbench' on the Perry website. I'm expecting these to be released at the end of this month, so until then this model will go on the to-be-completed shelf (with some others). I'll post final pictures when it's all done.