About 2 years ago I had pots in a group pit firing and got some good results. No place to dig a pit at my place, so I decided to try barrel firing. A recent video on Ceramic Arts Daily by Sumi also got me "in the mood" to give it a try. Here are some pots I made using a few different types of clay I had on hand, with terra sig on them, bisqued to ^019.
The terra sig. recipe I used is from Clayart.
500g OM4 Ball Clay
1000g EPK
14 cups water
2 tsp Trisodium Phosphate
2 tsp Trisodium Phosphate
Let it settle for a few days, siphon off water on top and about the top third of terra sig. This is white terra sig. You can make different colors by adding stains and oxides. I may get to that if my firing pleases me.
As for the stuff to color the pots, I followed Sumi's advice. I'm using alot of table salt, dried coffee grounds, horse stall bedding brined and dried corn husks- lots of those from eating great corn this year! I did have alot of luck with newspaper saggars in the pit firing, and since I haven't saved absolutely tons of stuff, I will use these items in my newspaper saggars. Also, I have used Miracle Grow and copper oxide in the past, so I'm throwing that in, too.
Figuring out how to dry the coffee grounds and husks without bugs galore was tricky, but a baby pool and stroller cover came in handy. Now I know why I never got rid of this stuff! A few days in the sun and we're good to go. 
I loaded the kiln yesterday, but it was kind of rainy, so I will fire today. There are holes in the bottom of my barrel and some bricks and a grate- I decided to leave the very bottom empty for air flow...no big reason. I layered paper, wood shavings, horse stall bedding, salt, miracle grow and saggared pots- 2 layers, about 9 pots in all. Wish me luck.
