Head space in Weck jars I splurged and bought some Weck jars for canning.   I purchased the .5 liter tulip jars.   I notice that they have a substantially larger mouth than Ball/Kerr jars.  They also appear to be both fatter &amp; shorter.   I tested with my canner, and can get only 5 jars per level instead of 6 jars with the Ball pint jars.
Does the difference in shape mean any changes I should adjust any recipes from the Ball Canning book?  I am particularly wondering if the head space should remain the same.
I use the cylindrical jars from Weck and would say that the headroom can be kept the same in general. At the end of the day you just don't want any stuff to swell over and not have too little in there so it spoils.
In my experience keeping about a fingers worth of space to the rim will not cause you any major issues.