The gun is designed to fire standard handgun rounds, using interchangeable barrels for different calibers of ammunition.

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They also point to the fact that lead's main alternative, copper, is more expensive and isn't available in all calibers.

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The printed gun seems limited, for now, to certain calibers of ammunition.

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We set goals of all calibers for ourselves every single day (heck, this morning I set a goal to remember to eat breakfast).

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