Anyone using Variability and/or Limits to audibly discern screw caps?

[adkelley]

One liter bottle screw caps around here come in at CO 38-41 and even higher for the larger caps. I'm curious if anyone has experimented with adjusting the variability and/or limits to help audibly discern them? If so, what's the number(s) you've chosen that helps you differentiate a coin from a screw cap or other junk targets?

One trick that works is to lift the coil ~6 and if it still sounds off then you know its a screw cap. Problem is this trick can really slow you down in an area with lots of screw caps. So I'm hoping there's a way to discern them strictly through audio.

Thanks
-Alex

[coinnut]

I've never found a way to get rid of them, but I hunt in 2 tone now, and I hunt colonial cellar holes. That's how I elimimated the screw cap problem. lol Not many screw caps out there. The bad part is that them CO numbers are smack in the middle of Indian and Wheat cents, not to mention countless other keepers. Someone who hunts parks may have figured out a way, so stay tuned. I mighty be tempted to just go by the depth guage on them, but that may lose some coins as well.

[Epi-hunter]

Depth is the only way I can really tell.

Some people I know can tell a difference in tone quality though. :-\

[Dug D]

I wish I could help, my x-50 does the same thing, screw caps usually hit harder but I end up digging them. I do have less problems with the concentric coil.

[adkelley]

Thanks guys. Well I just got a pair of Ratphones to complement my Gray Ghosts and took the opportunity to test them by making changes to variability settings at home using coins and screw caps. If air tests are any indication, then I'm afraid that determining depth or raising the coil are the only reliable solutions to discerning screw caps in the field. One exception though; when a screw cap is on edge, the audio tends to be a smear of several pitches, like a shriek, while moving the coil. I tried this with a coin on edge and compared to a screw cap, the tone has a fairly solid pitch, primarily because the edge of coin is much smaller in width. Hope this helps

-Alex

[Jason in Enid]

You're not going to be able to eliminate them without loosing coins. If you are only looking for deep targets, thats one thing. But if you are hunting for coins in general, then you will have to dig the caps as well.

[adkelley]

Thanks Jason. I agree with your opinion. If you're digging all coins, no matter what depth, then you have to dig the majority of screw caps as well. But typically I'm after the old, deep stuff. The exception is quarters, which I'll dig no matter what depth.