I'd ask this in a comment but I don't have enough reputation
- What weapons are you using? - I prefer 2 lmg's (if you're level 50)
- What perks are you using?
- At later levels, the self-revive is pretty much useless, because the enemies have so much armor, there's no way you can kill them with a pistol (before getting killed).
- The reason why I prefer 2 lmg's if you're level 50, is because that's when you get Sleight Of Hand in survival. That's really op with 2 lmg's.
- The other perk is your personal choice, you can take the self-revive (it's still good if playing with a friend because of the extra time you get) if you want, but i prefer Steady Aim or Quickdraw.
- Where does all your money go?
- If you follow these instructions, you should have a decent amount of money at round 24, 2 lmg's are worth of 14 000 + attachments (I prefer red dot sight and grip).
- Riot shield group is good IF you know how to use them properly, they can't stand outside of the house, the helicopters will shoot them down. So don't waste your money on that every time they get killed unless you have a sentry gun (that doesen't shoot in a position the riot shield guys are).
- What level are you?
- Like I said before, you need Sleight Of Hand. It's just that great.
Now, if you are level 50, you have 2 light machine guns (MG36 or MK46 and L86 LSW are my favourites), Sleight Of Hand, some claymores in your pocket (and air strike/predator missile, i prefer air strike because you can just throw it out of the door on your left and everyone camping there dies/takes damage and you don't risk yourself by controlling the predator missile, which probably won't hit the target if it's middle round since there's enemies shooting at you) what you need to do, is just go in the house at the middle and just camp behind the sofa. (Or behind the table, requires more skill but it's better if you believe you can handle the people coming from the door on your left).
Put the claymores outside the door and the usual cover spots the enemies use inside the house.
When you run out of ammo, switch your weapon. There's no reason to reload if you have another lmg with full ammo. When you run out of ammo in that gun, then reload. And remember, you have Sleight Of Hand.
IMO This is probably the best strategy there is, if you still can't do it, just practice more and try again.
Oh, almost forgot: You'll also need flashbangs. Not to blind the enemy so you can shoot them without getting shot, you should find a cover to do that. But so you can run pass them if you need some ammo/armor.
Hopefully this was helpful.