I was doing some landscaping in my yard in Pennsylvania and found a pretty large bullet casing in the mud. It's rusted, but the headstamp is still surprisingly clear. My house was built in the 1910's.
I think 'DWM' means Deutsche Waffen und Munitionsfabriken? But I can't find any information on the 'K'. I'm unfamiliar with ammunition and not sure what type of bullet this even is. Any help would be greatly appreciated!
The K indicates that it was produced at the Karlsruhe, Germany DWM plant. I think the cartridge may be 7mm Mauser aka 7x57mm.
That looks like you actually have an intact round there. Be careful with it.