Here is the full list of all 30 Guncraft: Blocked and Loaded achievements worth 1,000 gamerscore.
Destroy 100,000 blocks.
Destroy 1,000,000 blocks.
Destroy 10,000,000 blocks.
Build 10,000 blocks.
Build 100,000 blocks.
Build 500,000 blocks.
Get 5 kills without dying.
Get 10 kills without dying.
Get 20 kills without dying.
Win a match using a class with no bonuses or killstreaks in it.
Kill 100 enemy players.
Kill 1,000 enemy players.
Kill 10,000 enemy players.
Collect $100,000.
Collect $1,000,000.
Collect $5,000,000.
Freeze 100 enemy players.
Freeze 1,000 enemy players.
Get 10 kills between you and your gunner in a single tank.
Destroy an enemy helicopter and watch their snowy body fall into the lava.
Hit somebody with the Bunker Buster itself.
Capture the flag 100 times.
Reach wave 10 in Onslaught.
Reach wave 25 in Onslaught.
Win a 16 player race without using any powerups.
Win a 3 round Spleef match without anyone else scoring any points.
Kill 200 Zombies or Lunatics in Paranoia.
Kill 50 Queens in Paranoia.
Re-Craft for the first time.
Kill 100 enemies with your AI SAM Site or Turret.