Unlimited T-7 Bombs
In most of the magazines there are boxes with t-7 bombs in them go up to the box and get the bomb. Open it again and you will get another bomb. They are unlimited but you can only carry 20 t-7 bombs. This trick will work in almost every box that holds the t-7 bombs.

Pop Heads
Unlike Resident Evil, Carrier's fine aim allows you to see where you aim at on a zomebie. Attack the head as much as possible to increase the chance a shot will "pop" the zombie's head, saving you valuable ammunition.