From the photo, it look's to me like he is using way to much hull material to turn the crimp. I use a roll crimp a lot and turn just enough to roll the edge over. Probably just under 1/4 inch and I do not use friction (heat) to set the crimp. Heat causes the plastic to turn brittle and make the hull very hard to open easily. I have reloaded nice shot and not experienced any problems with crimping the hulls. Using Cheddite plastic or paper hulls I have never experienced that problem and my fired hulls can be reloaded by hand rolling them on a wood dowel to even out the hull mouths. Too much material in the crimp and too much friction to set the crimp is my thought.
