After learning investigators needed DNA from parents to help identify the victims of the Uvalde school shooting, Dr. Vin Gupta breaks down how lethal an AR-15 style rifle can be to the human body.  » Subscribe to MSNBC: http://on.msnbc.com/SubscribeTomsnbc About: MSNBC is the premier destination for in-depth analysis of daily headlines, insightful political commentary and informed perspectives. Reaching more than 95 million households worldwide, MSNBC offers a full schedule of live news coverage, political opinions and award-winning documentary programming -- 24 hours a day, 7 days a week. Connect with MSNBC Online Visit msnbc.com: http://on.msnbc.com/Readmsnbc Subscribe to MSNBC Newsletter: MSNBC.com/NewslettersYouTube Find MSNBC on Facebook: http://on.msnbc.com/Likemsnbc Follow MSNBC on Twitter: http://on.msnbc.com/Followmsnbc Follow MSNBC on Instagram: http://on.msnbc.com/Instamsnbc #MSNBC #Texas #SchoolShooting