I went to a sand box the other day to start playing around with making stuff. I had seen a fireworks display earlier and had liked the effects they had achieved. I thought that even bigger would be better, and since I had not seen any true artillery pieces around I decided we needed some. I started off small with a medium-sized mortar. I made a cylinder and shrunk it down to be the baseplate. I made another cylinder and hollowed it out to be the tube. I attached the two, tilted the tube to about 60 degrees (1067 mils), and made a couple of legs for it. I painted it the color of asphalt and voila! In about 10 minutes I'd made something that anyone could easily identify as a mortar.
The next part was the ammunition. I'd purposely made this larger, with the intention of shrinking it down to the correct size once I was done. It was much trickier to make than the mortar. The body of the round was pointed on the front and tapered on the back, there were stabilizing fins and a fin guard along with the propelling train. This took about an hour, but I learned much more while making it. I painted the round the same asphalt color but when I tried to shrink it it would only go down so far, too big to fit in the tube. I probably could have fiddled with it and gotten it to fit, but I decided I'd had enough fun with that for the day, saved the round in my pack but left the mortar there to be recycled.