The rate of twist is 15 to 1. To slow. Accuracy suffers a little. But at legal self defense distance this is no issue. I have had MANY GLOCK hand guns and they are the finest hand gun you can own. Glock 20 n10mm is my all time fav. For conceal carry when your life and your family members lives are on the line. Glock is the only choice. My choice-Glock 32 in 357 sig.