At the bottom right of the Ammo Display on the Rogue Alley page is a red hand gun, click that to pull up the gun selection page.

You can change your gun once, and only once.  

A little bit of knowledge:

All the guns are the same, the only difference is sound, use what you enjoy.  THe smallest gun, the largest gun, the slowest, the fastest, they all do exactly the same.  There is no difference other than cosmetic.

Every gun gives you 6 shots.

1st shot = 10 bullet burst.  If you land 10 bullets in the big glowing red target, you got 10.

2nd shot = 8 bullet burst.  If you land 8 more bullets in the big glowing red target, you got 18.

3rd shot = 6 bullet burst.  If you land 6 more bullets in the big glowing red target, you got 24.

4th shot = 4 bullet burst.  If you land 4 more bullets in the big glowing red target, you got 28

5th shot = 2 bullet burst.  If you land 2 more bullets in the big glowing red target, you got 30.

6th shot = 1 bullet.  If you land 1 more bullets in the big glowing red target, you got 31.

A grand total of 31 bullets.  If you land all 31 bullets in the big glowing red target, you got 31.

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Every gun is the same.

Every gun shoots the same distance.

Every gun shoots the same speed.

Every gun reloads the same speed.  

Every gun shoots the same accuracy.

Every gun shoots exactly the same as the gun next to it.

The only difference is the cosmetic animation that plays on your side.

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