Growing carrots in large barrels

I am growing carrots in containers for the first time.   I am using 100% ordinary soil (not recently manured soil).   My soil is a light friable loam but not in the least sandy.

I want to do the same, but I need to find something to put them in 1st.. grrr

It's odd that you all seem to be avoiding sand in your soil mix, as sand allows the roots to really grow. I'm adding as much as I can get hold of (which isn't as much as I'd like). If you check the Medwyn Williams section under John's NVS section, you'll find that he grows his prize carrots in lots of sand, and as a 10X winner at Chelsea, he must know something. You lot aren't growing for Chelsea but the general info would certainly give you very decent carrots for home.

found some "things" I can use on a dump and will add half soil and then the rest compost..

"Buy"

Please explain this word, I am unfamiliar with the concept  

Done it. I used an old plastic dustbin. drilled drainage holes in the bottom. put around 3 shovels of sand into the bottom, then alternate sand shovels and soil shovels, until i nearly filled the bin, then i put aound 5 inch of compost on the top, then scattered my seeds and covered with around 2 inch of more compost, I then watered it. Hope this is kind of the right thing to do. But i also dug a trench,( around a foot deep) half filled with sand, then 4 inches of soil above that, scattered my seeds then with 2 inches of compost. Hope these two work  

I,m growing my carrots in one of those bulk bags that you can buy sand in. I filled it with compost out of an old compost bin that is falling to bits. I,ve built a new wooden bin and am using this for a new mix. After carrots have grown in bulk bag I will use compost during autumn digging.