Gun cheats and cheat codes for Xbox 360

Unlock Nock gun:
Finish story mode to unlock Magruder's seven barrel Nock gun. 

Unlock Nock gun + armored horse:
Finish story mode and all sub-missions to reach 100% completion. 
This will unlock Reed's armored horse and Magruder's Cannon Nock gun. 
The armoured horse cannot be killed and if ever lost, it will return to the mine.

Unlock 69 Ferguson Rifle - Beat Hollister to get this weapon.
Unlock Apache Shirt - Finish the Hunting missions. 
Unlock Cavalry Sword - Beat Reed. 
Unlock Dual Peacemakers - Beat Hoodoo Brown.
Unlock Silver Spurs - Finish the Pony Express missions.

Get unlimited ammo:
Pick up a TNT from the Badlands mine. 
Go to the abandoned house in the Badlands, where the buffalo graze. 
Go to the back of the house on the outside. 
Face the chimney (west) and place the TNT barrel on the left side of the chimney. 
Blow up the TNT,  to open a hole in the ground, with ammo for all weapons. 
The ammunition will reappear again after you leave the area. 

Unlimited health:
Go to Dodge City. 
Go to the lower part of the bridge. 
Follow the path on the other side to reach the cave. 
You will find a life power-up which will reappear again if you leave the area. 
Note:You can find ammunition and money also in the cave. 

Another way to obtain health:
Go to the Indian Hunter's hut.
Go to the building to the left of the hut, with the stairs going up the side. 
Go up the first set of stairs, and continue going straight. 
You should see a spout-type object coming out of the side of the building. 
Jump onto that spout, and walk toward the wall of the building. 
If done correctly, you should go through the wall, and into the inside of the house. 
There is only a small ledge for you to drop onto inside, so move slowly. Once 
inside, look to your left and you should see three whiskey bottles on the ground. 
You can pick these up as many times as you want.

More health:
Go to Hecht Ranch, after go to the shack next to the windmill. There you will find 3 
whiskey bottles. You can pick these up as many times as you want.

Easy money:
If you capturing bounties alive on the bounty hunter side missions, you can get 
more money. The wanted poster that offers more money if you capture them alive.

You can do this with the following trick:
Kill all the bodyguards or gang members. 
If the bounty is on a horse, first kill the horse. 
Get close and melee attack. 
This will stun the fugitive and present an opportunity to grab them using LB. 
After, press X to subdue the fugitive. 
This will awards you more money for each bounty. 

If you press LB accidentally and release him, you can try to melee him and grab 
him again. But don't forget, if you do this too many times or if he has been shot, 
you may kill him and get less money. 

How can ride faster?
Hold Dash, while repeatedly jumping your horse.
This will double the speed. 

Ending of the poker cheating:
When playing Texas Hold 'em after the tournaments in the Alhambra, you will no 
longer have the option of cheating.