Early fruits of the forest

Am staying down on the south coast on the edge of the New Forest.  Although the blackberries are only just ripe here the sloes are soft and ready for the freezer.  I feel a sloe gin is in order.

Talking of which - has anyone ever had their sloe or damson gin turn into jelly?  What have I done to make it do so.  It tastes fine but... 
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