Identification German WWI Artillery Shell casings brass and steel

Hello and thank for taking time to read this. I bought two shell casings at an online auction, one brass one steel, they seem to be from the same caliber, possibly 77mm? Any identification help would be much appreciated, thank you!

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I was told y'all might be able to help ID this shell casing. I know it's German but that's about it. Can anybody tell me anything else? : r/EOD

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