Also, If you are picking strait up and strit down on the rod for your cast, you can also try lifting you rod away from your body. This will change the axis of your line just enough to not let your loop catch the tip.
Again a subtle change will make a big difference so start with small adjustments.
Regardless of what you try, your line should not be getting caught up. If it is then you need to change your style and mechanics. If I were to cast 100 times, only a couple would get caught up as you have described. When I do get caught up is when I have alot of line out, and my timing gets off.
Let me know how this works!!