Maybe, but it's not likely the issue since guys have no problem spinning boards like the ShredStixx Custom with 4 full-size fins, or a Flyboy with 2 full-size and 2 twinzer fins.
Post some vids of your unsuccessful attempts so we see where you're getting 'caught up'...I have a buddy who's had a tough time landing a 3 for the past 3 years. When he gets to the 270º mark, he's all twisted up/off axis and diving into the water.
3's require some weight back, and you should always learn by dragging your back hand in the water off the toe edge, to help you start that spin...you really only use that move to spin the first 180, then use the wave's push to help bring you around.
As you start to come back around, you may even use that back hand to help stop yourself from spinning and then punch that front arm forward like Superman right at the corner of your weighted boat.