When Games Workshop switched from HMG to a french manufacturer, they changed the bottles and those bottles seem to leach water over time which is why they dry up. Their new chinese made bottles seem better.
Mike
Hmmm... yeah, but it's actually the same bottles with a different lid-system - I you screw off the lid of a 'bolter-round' and the black part of a new one, the containers are completely identical... at least to my eyes....
To sound horribly pedantic, there's a tiny difference with those little tabs at the bottom of the pots, the ones that aid stackability. The old pots don't stack well on top of the new ones because the tabs weren't designed for them.
If that doesn't win me an LAF "Nitpicker of the year" award, I don't know what will.