Some rifle calibers with extreme velocity in custom barrels with fast twist (1:7 or 1:9) place such high rotational speeds on the bullet when it exits the barrel at @ 3700fps. and 370,000 rpm can cause a bullet to vaporize or lose its copper sheath and the lead or steel core may or may not remain intact. Even solid copper bullets have their rotational limits. This is not common in any factory ammunition and not in a .223/5.56 caliber. Depending upon bullet weight a .223 will be from 2,500 to 3,000 fps depending upon bullet weight. Most factory 55 gr .223 ammo is @ 2,900 fps. Factory ammunition is never at hyper velocity to cause a bullet to rip itself apart.
Hand loaders are aware of this with lighter bullets for target shooting and varmint hunting. You can load some .223 36 gr bullets with compressed powder loads to 3,700fps. For a long time introduced in 1935 the 220 Swift was the king of speed with 50 gr bullets exceeding 4,000fps. Loading to such speeds wears out barrels fast however.
So no Ray you imbecile the bullet did not fragment, detonate, or shed its copper sheath. It hit Trump's ear, went through the body of a supporter in the stands, and blew up on video as it hit the railing or took out the hydraulic cable of the heavy lifter to Trump's left. The video's show two bullets to Trump's left where one hit the stand rail and one hit a hydraulic hose. In either case one bullet was photographed with a high speed camera after it hit Trump and than as it hit the patriot in the stands and than the rail or the hydraulic line. Crook was using factory ammo. This factory ammo killed one innocent hero and wounded two others. What contemptibility from the FBI. Every hand loader and target shooter is reading what Ray said and shaking their heads in disgust.
Bingo.
If one has a 1:7 twist, a 55gr projectile is spinning a bit higher that what it was designed for. The risk is higher that it will fragment with respect to a 62gr bullet made for those angular velocities. There are graphics out there addressing this for the 556 in terms of twist vs. bullet type that should be used.
Regardless, how do you run ballistics on a fragged bullet unless you find a substantal chuck of the jacket? Highly doubtful.
Maybe he used frags. Who knows.