Achievement hunting!

I have a few achievements missing from Halo Reach but I am unsure how to get them in multiplayer. The problem is getting into the game modes on the right map.

The achievements are.

Paper Beats Rock
Defiant: Assassinate a player that just exited Armor-Lock in a matchmade game.
15

All Alone
Defiant: Be the last surviving uninfected player in a matchmade Infection game.
10

Emergency Room
Anniversary: Infect 3 players in a single round in a matchmade Infection game.
15

Bounty Hunter
Anniversary: Capture 10 skulls at once in a matchmade Headhunter game.
75

Can anyone help?

Open lobby for achievements tomorrow 9pm est. pm for invite if interested.

If somebody wants to do it now i’m up for it :stuck_out_tongue:

Play with a full team of friends with the map packs to immprove your chances of pairing up with others with the map packs.

TIP:
This is something that i did. Once i completed all of the achievements that attained to a paticular map pack i moved it to an external hard drive to reduce the chance of playing on that map pack. Helped me get the achievements.