Modern motion-based metal detectors are more prone to allow some iron to break past the discrimination setting than the older VLF-TR discriminators. The reason why the world went to motion-based discrimination anyhow (back in the early 80's) is because the motion principle takes less user skill and because it gets much better depth on nonferrous targets in most soil conditions.
Among motion discrimination discriminators there is a lot of variation in just how the signals are processed, nowadays mostly in software rather than in circuitry. The systems in the Bounty Hunter Titanium models are designed for quick response and good target separation combined with good sensitivity.
With a bit of experience you may become skilled in distinguishing iron breakthrough sounds from real nonferrous targets. Iron breakthrough is usually choppy and inconsistent esp. if you change the direction of the sweep over the target, and the location of the target may seem to wander all over the place. A nonferrous target will tend to be more repeatable and seem to remain in one spot. But sometimes you'll find an iron/steel target that just plain sounds like a good target. Iron rings (for instance harness hardware and buckles) will almost always pop through the iron rejection. Flat pieces of iron/steel laying horizontally in the ground (flattened tin cans, steel bottlecaps) will often sound and ID good but if you turn the searchcoil into the vertical plane and sweep over the target it will usually drop back down into the iron range whereas a coin will usually remain in the coin range. The old "square" (cut) nails and bent regular nails tend to break through more than straight modern nails.
Since you're new to metal detecting, I would suggest not giving up on the machine you've got. All metal detectors are a compromise between finding the good stuff and ignoring the bad stuff, and what you've got is an example of a fairly good compromise. Get some more experience with it, and be willing to dig questionable signals just to find out what they are so you can learn what the machine is doing. If it turns out you like the hobby and think you might want a better machine, this extra time and experience on the machine you've got will help you better understand what other users are talking about (on the forums or in person) and you'll be able to make a better informed choice on your next machine.
Our more recent Omega and in-the-process-of-being-released G2 (both Teknetics products) incorporate some tricks in software to help with iron rejection while still letting the good targets come through. The Omega has been out there long enough to get a very good reputation among users for its ability to work in the iron trash. I expect the G2 to be even better in that regard, but user experience will have to be the final judge of that.
--Dave J.
Chief Designer, FTP-Fisher
