paraffin shrinkage

Hello! I'm a total newbie and need a bit of help! I can't figure out or find out how to stop these big air pockets happening on taper candles! I'm using kerawax 4600 pillar paraffin wax. Would a different type of wax be better? is there a pour technique I need to know about? Thanks in advance xx

I am pouring paraffin and Vybar mix into 6,5 cm cylinder glass mould. As you can see from the picture below, a very deep shrinkage well does form (whole chilli fits inside). What are the techniques (like mould pre-heat, pre-cool, pour temperature and etc) or additives do reduce this shrinkage...