Back when I was a young'n, I learned to cook on a Santa Maria grill, and they old fellers used a concrete water culvert section, that looked a lot like that burn barrel, except it was concrete and very old. It worked great, they burned down the red oak in the kiln, and we (me, actually) moved the hot coals to the grill unit. It was direct fired, also made from concrete culvert, and you (me) shoveled the coals into the bottom through a hole.
Oops, yes it worked great, and a useful addition to the setup.
Oh, and if you leave the shovel in the coals in the kiln, it will light the handle on fire