grenades in the woods

My search buddy had a whole lot of stuff he wanted to show me. So I drove to some place around Maastricht, and then we hiked for 30 minutes into the woods. He had found around 150 grenade parts here before and he still had a lot of space that was undetected. Every half a meter would beep and there were parts of 2 kinds of grenades everywhere. THey are supposed to be from after WWII and used for practice although we are not sure. I didn’t find the head, but he did. I am now soaking the parts in demineralised water for the next 3 months.. I’m no good with waiting but anyway.