Here is the full list of all 81 Lead and Gold - there are Gangs of the Wild West achievements.
Win 100 matches involving sacks of gold.
Deliver 720 sacks of gold.
Conquer 720 zones.
Win 100 conquest matches.
Win 300 Matches.
Win 100 powder keg matches.
Destroy 180 Objectives.
Revive 720 gangmates.
Win 30 conquest matches.
Destroy 60 objectives.
Destroy 60 Objectives.
Kill 720 enemies with dynamite.
Win 30 matches involving sacks of gold.
Deliver 180 sacks of gold.
Win 100 matches.
Perform a Grand Slam (kill 4 players within a short amount of time) in any multiplayer match.
Kill 180 enemies with dynamite.
Trap 720 enemies.
Kill a developer.
Kill 3 enemies with a single dynamite blast.
Kill 2000 enemies.
Kill 180 enemies with your sidearm (Gunslinger's revolver not included).
Revive 180 gangmates.
Conquer 180 zones.
Kill 60 enemies with your sidearm (Gunslinger's revolver not included).
Collect 8 sacks of gold in a Goldfever (COOP) match.
Trap 180 enemies.
Shoot off 4 enemy hats in a row (without dying or killing them)
Kill 7 enemies with headshots in a row (without dying)
Kill one and only one of each archetype in a row (without dying)
Kill 300 enemies using fanning.
Kill 900 enemies using fanning.
Destroy 20 Objectives.
Tag 800 enemies.
Deliver 30 sacks of gold.
Shoot off 250 hats.
Kill 1000 enemies.
Conquer 30 zones.
Tag 250 enemies.
Revive 30 gangmates.
During a multiplayer round, gangmates kill 10 enemies tagged by you.
Tag 40 enemies.
Tag 20 enemies during a multiplayer round.
During a multiplayer round, teammates kill 5 enemies tagged by you.
Trap 30 enemies.
Killl 30 enemies with dynamite.
Kill 20 enemies with your sidearm (Gunslinger's revolver not included).
Play a multiplayer round without getting killed or knocked down and kill at least 8 enemies.
Kill 25 enemies with the coach gun in a multiplayer round.
Shoot off 100 hats.
Revive 12 gangmates in a multiplayer round.
Kill 15 enemies with dynamite in a multiplayer round.
Perform 10 headshots with the Buffalo rifle in a single multiplayer round.
Catch 10 enemies in your traps during a single multiplayer round.
Kill 6 enemies caught in traps in a single multiplayer round.
Kill 3 enemies caught in your traps during a multiplayer round.
Kill 3 enemies with a six shooter without reloading in a multiplayer match.
Be the player delivering the most sacks to base during a round. Repeat 3 times.
As the Gunslinger, deliver 3 sacks of gold and kill 12 enemies in a multiplayer round.
Deliver 4 sacks of gold in a single multiplayer round.
Attain rank 9 in a multiplayer match.
Kill 50 enemies using fanning.
Rack up 30 kills in a multiplayer round.
Finish off 20 knocked down (KD) enemies in a single multiplayer round.
Shoot off 15 hats in a multiplayer round.
Shoot off 20 hats.
Perform at least 8 head shots in a single multiplayer round.
Play a multiplayer round without getting killed or knocked down and kill at least 4 enemies.
Kill 20 enemies with fanning in a multiplayer round.
Kill 3 enemies within 12 seconds using fanning.
Kill 250 enemies.
Die 300 times.
Rack up 20 kills in a multiplayer round.
Revive 5 gangmates during a single game round.
Die 150 times.
Play all release maps.
Score a long range headshot.
Revive a gangmate.
Finish off 10 knocked down (KD) enemies in a single multiplayer round.
Win a match.
Kill an enemy.