|A Killer in the Family (1983) [John Lyons]: Reportedly shot to death (along with Susan Swift and Amanda Wyss) by Robert Mitchum and Stuart Margolin after Robert and Stuart steal their car. (I haven't seen this movie myself.) (Thanks to Robert)
Full Metal Jacket (1987) [Pvt. Cowboy]: Shot in the chest with a sniper rifle by Ngoc Le as he tries to radio another unit.
Tequila Sunrise (1988) [Gregg Lindroff]: Reportedly shot in the head by Raul Julia. (I haven't seen this movie myself.) (Thanks to Nick and Gary)
The Lost World: Jurassic Park (1997) [Peter Ludlow]: Eaten by a Tyrannosaurus Rex. (Thanks to Nick and Gary)