It can take a while to die form peritonitis. I’ve read Civil War stories were a wounded gut shot vicitim can last months. Some even lived.
Not exactly the poor, oppressed “indigenous peace loving people” they’d have us believe.
The Comanches ranged from Texas to the Dakotas, East to the Tennessee Valley and west to New Mexico for one purpose - Torture and MURDER. The fact that 1883 portrays them any other way is Hollywood revisionism at its worst