This video, produced by the Federal Law Enforcement Training Center, shows how different shotgun rounds impact ballistic gel. They show standard rounds as well as specialty flare and breaching rounds and the exotic bolo, flatteche and dragons breath shell.
Flare rounds look nasty. They do not look like they would kill, but they have enough energy to embed themselves in soft tissue and burn inside the body.
Hat Tip: Migs at MP.net