Bill. Try to get a copy of the August 2012 issue of Precision Shooting. There was an article testing different coatings MS2, HBN, WS2 and Lubalox on Nato 223 bullets and it was co-authored by Cadets at the United States Air Force. Maybe you can try digging it up on line. I did years ago. It was very interesting reading. If I remember correctly HBN lowered friction the most but by very little. In fact I believe the friction percentage was really low like 10-15 percent is my memory serves me correctly but don't hold me to it. Look it up for yourself.