I recently purchased a Marlin 880SQ rifle.  This is a bolt-action, heavy-barrel, .22LR bolt action rifle.  It is designed mostly to be a good reliable squirrel rifle.  

Anyway, I went to the range the other day and sighted it in at 25 yards.  Most groups were around .75 inches or so (it was windy).  However, I noted an odd behavior when I would shoot CCI stingers in the rifle: the first round out of the mag would fly high and left.  The rest would make one ragged hole about .3 inches across.  And this is after firing about 100 rounds through the barrel!  Has something like this ever happened to you?