I was reading a thread a while back how someone said a 9MM is more powerful than a .38special round is that true? The case length on a .38sp is 29.3mm which means more powder in the shell than the 9MM shell Case Length which is 19.15mm. The .38special shell holds more powder whether they are both FMJ or HP rounds and the weight/gr of the two i you got to factor those in. I usually shoot .38sp out of my S&W .357magnum and 9MM out of my Glock 17 or other 9MM'S I feel a difference between the two. I thought the .38sp was a more powerful round than the 9MM??? I always factor in who has more Powder backing them the diameter is almost the same. ???????