I use the 1/2 pint wide-mouth jars and find that I get up to 4 oz. in the jar if I pack the tobacco pretty tightly, depending on the cut of the tobacco. Most tobaccos that come in 100 gm. tins fit well into the 1/2 pint jars. I put flakes, plugs, or cakes into the 1/2 pints loosely.
While I've used the pint jars on occasion, I find that the tobacco on the lower part of the jar becomes a bit too dry once I re-open the jars & start consuming the contents. This is much less pronounced with the 1/2 pint jars.