Lugers tend to throw brass fairly vertically if you hold the gun straight.
A large bright color fiberglass reinforced vinyl tarp will help make it visible. Think orange.
Some use a nut roller to pick it up more quickly. Something like this:
https://www.amazon.com/Garden-Weasel.../dp/B0042U6GE8
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Igitur si vis pacem, para bellum -
- Therefore if you want peace, prepare for war.