In Red Dead Redemption for the PS3 and Xbox 360, there are a couple cheats you can turn on to get quite a few more guns (assuming you don’t already have them all). Once a cheat is turned on, you won’t be able to save your game and you won’t earn achievements, but you CAN show off your “nice shootin’ Tex!”
To turn on cheats, go into Options, select Cheats and hit the Y button on the 360 or Triangle on the PS3 and enter the following code:
IT’S MY CONSTITUTIONAL RIGHT for gun set 1
and/or
I’M AN AMERICAN. I NEED GUNS for gun set 2