[newbie] Cannon barrels color

Look fairly black to me:

IF you go to this site:

I'm building a Revell kit of german battleship Tirpitz. Instruction papers show all cannon barrels are to be painted with the same color of the ship's hull, that is (depending on the section) a light, sea or tank grey. On the box image, on the other hand, all cannon barrels are shown as black. Which color is the true one? Were cannon barrels really painted as the rest of the ship, or where they darker? Black cannons surely would look better on the finished model, but I want to paint a realistic Tirpitz. Thanks in advance,

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I'm building a Revell kit of german battleship Tirpitz. Instruction papers show all cannon barrels are to be painted with the same color of the ship's hull, that is (depending on the section) a light, sea or tank grey. On the box image, on the other hand, all cannon barrels are shown as black. Which color is the true one? Were cannon barrels really painted as the rest of the ship, or where they darker? Black cannons surely would look better on the finished model, but I want to paint a realistic Tirpitz. Thanks in advance,

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