Large Barrel

 is an item found in Red Dead Revolver.

Description
"Whiskey barrels have also proven to be effective as body armor."

- Store description

As with all similar items, the is not used in the game beyond unlocking a showdown character and journal page. The store description references the fact that Cooper wears a barrel around his torso as a form of shield.

Unlocks

 * Cooper as a multiplayer character in Showdown Mode.
 * Pages 112 - 113 of Sheriff Bartlett's Journal, covering Cooper.

Merchants
The can be purchased from the Shop interface at the start of the mission "Fort Diego". If not purchased, it is not available subsequently during the current game.

Since Cooper is also unlocked by completing the mission "Rogue Valley", which occurs before "Fort Diego", the Large Barrel should always show as sold by the time the player has an opportunity to buy it.