Test Driving the CP-100 Pinpointing Probe How well this metal detecting pin pointing probe works

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My CP-100 Cache and Coin pinpointing probe arrived eight days after ordering it from Kellyco for $129.00 (free UPS ground shipping.) It was well protected inside two nested boxes with more than sufficient padding.

The unit came with a warranty card and a two-page instruction manual. There was a battery already in the pinpointer and it worked perfectly first time out of the box.

The pinpointer is extremely sturdy. The handle is made from 1/8th-inch by 1-inch aluminum that feels as rigid as steel. The 8-inch long stainless steel probe is solidly mounted to the body. You can grab the shaft and flex it without any shifting of the shaft in the holder. The instructions state that this detector is not intended for prying, but it's so strong that I'd be tempted to do so.

The business end of the shaft (shown here full-size) is chrome steel, waterproof, and designed to be pushed into hard ground. (The pinpointer's body is not waterproof.)

The hardest soil in my backyard is the walkway down the center of my test garden. It was laid out after a heavy rain and the soil is densely compacted. Nonetheless, the CP-100 stabbed into it with ease. I detected no flexure in either the shaft or the handle/body assembly. (The manual says that it you encounter rock-hard soil, all you need to do is make a starter hole with a screw driver.)

There are no ground balancing or sensitivity controls on the CP-100. All you do is pull the toggle trigger (visible on the bottom of the body in the second photo) and stick it in the ground. When the tip or sides of the tip come within 1/8th-inch of a non-ferrous object, the buzzer on the top of the body buzzes. The pinpointer is silent when the point is near or touching iron objects. But, the buzzer buzzes as the target goes past (again, after getting within 1/8th-inch of it) or when the probe is pulled away from it.

There are also slight tonal differences between ferrous and non-ferrous objects. When coming in contact or very near to a silver quarter it creates a bright, almost happy-sounding chirp. When passing or pulling away from a steel washer of the same size, the sound is slightly lower and plaintive, like the squeal of some small animal being stepped on.

Once the probe makes contact with a gold target, the alert buzz only remains on for two seconds. During this brief time, the loudness and frequency deceases rapidly. (In a way this provides a third discrimination mode.) Small gold rings, my wife's wedding band for example, do not cause the buzzer to sound.

Small lead balls are also problematic. Fifty percent of the time they don't cause a response. When they do, it's weak and like gold, quickly dies.

The pinpointer responds well to silver, aluminum, clad coins, and nickels. With these targets the buzzer remains on when contact is made. Large targets do not increase range or cause the alert to be louder.

So, what do I think of the CP-100 Cache and Coin pinpointer? I like it... with reservations.

The detection range is so short that for all intents and purposes the probe has to come in contact with the target to sound an alert. This is good because when you get a buzz you know exactly where the object is. But, it can take a lot of stabbing to contact small objects. I found locating something as large as a quarter can take a minute or two. The advertisement I read stated that, "The frequency gets higher as the target gets nearer," implying you can use this frequency change to steer toward the target. I did not notice any sounds or increasing frequencies as I probed around a quarter to help me steer closer to it. (If the tip comes within 1/8th-inch of a coin, the pinpointer makes a buzz that does increase in frequency as the point moves the final 1/8th-inch closer to make contact. But, this is such a limited range that I can't considered it as useful for steering closer to the target. If you're within 1/8th-inch of a target, I figure you're already there and don't need any steering.)

This would be a much better pinpointer if it came with an adjustable sensitivity that would let you increase the range to 1 inch to get close to a target, then dial it down for more exact pinpointing.

The extremely short range means that this probe is almost worthless for sweeping over a pile of dug dirt to see if the target has already been removed, or for sweeping the sides of a hole.

The response to ferrous objects is vague. If I was relic hunting and wanted to dig iron targets, this probe would be difficult to pinpoint them.

A vibrator option would be a good improvement.

Those are my observations of the CP-100 pinpointer. Please understand that this is the first pinpointer that I've ever used so my judgements should not be considered as informed or experienced.

I'm taking the CP-100 on a beach hunt 18 January. I'll post how it works in the field as soon as I get back.

(NEW!!! The final word after the beach test.)

I regret to say that after working with the CP-100 for a week in both my 50-target test garden and in the field, I have to conclude that its short sensing range of 1/8-inch makes it almost worthless as a locator/pinpointer. In the field, it failed to detect six different objects ranging from foil to coins to bottle caps, even after as many as a dozen probings in each case. I then resorted to hand-digging and sifting for the targets and found them faster that way that the time it took probing for them. I checked the probe after each target and it appeared to be operating correctly in that when very close to or touching a quarter it responded as indicated in the directions.

I believe the main reason I'm so disappointed with the CP-100 is that in the advertisement for it on the KellyCo site, the store from which I purchased it, stated that: "Speaker frequency increases as the coin is approached, indicating proper approach." While this is true over the detection range, the advertisement's failure to mention that the detection range is only 1/8-inch, which makes this claim pointless. Even when probing slowly, one covers 1/8-inch in a fraction of a second. For all intents and purposes the change in tone that's supposed to direct the user toward the target happens so quickly as to be of little value. By the time it occurrs, the user is already so close to the target, if he's been so lucky as to find it with the probe, that any further guidance is of little value.

In summary, the CP-100's range is so short that I find it useless as a pinpointing probe. Repeated tests show that it is quicker to dig and sift than use it. In grassy areas where digging and sifting isn't practical and this probe sounded like it would be ideal, I quickly lost patience after repeated probings failed to locate the target. In short, I doubt I will ever use it again, which is a pity considering the amount of money I paid for it.

From my experiences with the CP-100, and after discussing it in particular and pinpointers in general with the members of my metal detecting club, it seems that a pinpointer that will truly help detectorists quickly and easily locate targets should have the following two capabilities:

1. Like the CP-100 it should be capable of being pushed into hard soil.

2. It must have a detection range of 1 and 1/2-inches and be adjustable so that as the user closes in on the target, the range can be reduced for accurate pinpointing.

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