To make this as simple as possible, use this method:
1. Have 4 Real players; Be it You and 3 Guests/ You & Friends, Or any mixture :)
2. Load Survival
- Dead Centre, Mall Atrium
3. Take 1 Dummy Acc and take them all the way to the last floor of the stairs, Make them fall off slightly so they start hanging off, NOT DIE.
3. Give yourself Adrenaline and revive them, quickly make you dummy fall off and your main revive them again and repeat.
4. You roughly get 4 revives with 1 shot of adrenaline