Halo 3: campaign scoring problem?

Question

I am trying to get all of my halo 3 acheivments and I have to receive 15,000 points or 50,000 points for certain levels to get an acheivment. I put on fog, tough luck, thunderstorm, grunt party and IWHBYD, and catch skulls on. I put on the scoring set it to team so i can play co-op with my brother. Then i play the level get the certain amount of points, and get the points, and i never get the acheivment.......Why??

Answer 1

Whoever is the biggest contributor to the score gets the achievement. I had the same problem.

Answer 2

Yes you share points in campain but the achievement only scores individual points. If you score 15,000 all together but you yourself only scored 7,000 you would not get the achievement. You have to get up to 15k by yourself.