Is this on flooring, or tongue and groove planking?
Sales people can be mistaken! He may have had good results from another type of wood! Whereas, it appears that the gauge is too large for the type of wood that you have.The salesman recommended the 2in cleat nails. The wood is a 3/4 in x 5in cikel Tigerwood hardwood. We put in 3 rows and everyone has split.