Infinite ammo (sometimes)
Sometimes, it does not always work, but if you go to ammunation with one of the weapons that are used in the challenge. Once you beat the challenge (must beat it) there is a chance your gun will have infinite ammo. I have done it twice before. No ammo shows under the picture of the gun. Just like in the challenge. But the ammo is infinite. Please don't report this as bogus because it is not a 100 percent chance of doing it.
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