Originally Posted by
C-grunt
Basically. But nearly 50 percent more weight so there is more of the bullet when it does fragment. Also the longer bullet and thinner jacket causes it to fragment at much lower velocity than M193 or M855. Something like 2000 FPS.
Though I wouldnt really call it slightly longer. It's pretty significant. Here is a still shot of 55, 62, 69, and 77 grain bullets. Its from the video which I havent watched, just got the pics of the different bullets from it. A federal 55 grain FMJ has a listed length of .745 inches and a 77 grain SMK has a listed length of .994 inches.