I've had metal detectors since the 70's and use them to find 99% of my brass. I have a Garrett I bought at an auction in the 80's and another I bought at the LGS last year from a guy wanting to trade his, so I jumped on it for $100. A decent machine has discrimination you can set to where it detects just mostly your brass. At that setting it doesnt detect 22LR brass, and I can tell by the sound and meter if it's another metal. But I've used them a long time so I am experienced enough to use them efficiently, your results may vary. You can find good used machines for $100. Good luck.Thought about buying one of those under $100 metal detectors for locating brass in the weeds where I shoot. Got my kid talked in to trying it, but I have no clue how well it would work. Anyone here ever tried it? I know it would be a long time before it paid off, but isn't that the case with most anything reloading related?