[cthedaytrader]

I think what you are referring to is on the Sailfert test kits, with the titration kits such as Ca, the kit accounts not for an air bubble, but for the amount of reagent in the pipette tip, which is not accounted for in the syringe. So in this case there should be a gap of air between the plunger and the line. But on normal syringes you should get the air out.