I have noticed this as well. The Scirocco jacket is made of pure copper, according to their brochure, and appears to be much thicker than other bonded bullets. The thinner copper alloy used in the Accubond seems to foul a lot less - but is also more brittle and does not create the big wound channel of the Sciroccos. They are both good bullets - but the Accubond seems to have been designed to closely duplicate the terminal performance of the Partition; turnip-shaped wound channel with lots of penetration.