Mentos and Coke

I'm not sure what purpose shooting the bottle served, because it seems to me that the bottle would have exploded anyway from the pressure; but I could be wrong.
That's a cool little rifle anyway, so I'm not complaining.
Using the magnet was an ingenious idea. I'll have to try that, to see if it builds enough pressure to make the bottle explode. I saw the Mento & Coke geyser trick on Mythbusters and it looked pretty impressive, but I guess that doesn't necessarily mean it builds up enough pressure to blow up if it's enclosed.

Efficient Metal Detecting

If you are serious about treasure hunting, you probably have a metal detector or are thinking about buying one. But with over 150 models to chose from, which one is best? Which one will make the most finds? If any one model stood out, wouldn't we all be using it? While some machines clearly excel on certain types of site, overall there probably isn't more than a few percent to gain or lose on performance between models, once you get away from the low priced 'toy' range. You would be hard pushed to try out all the models available and frequently swapping from one model to another could not only prove very expensive but would undoubtedly reduce your finds rate, for maybe six months, until you become used to the machine.

Using a pair of good quality headphones always helps. You will hear fainter signals and at the same time, cut out distracting noise from your surroundings.

Then you could look at coil or search-head types and sizes. Wide-scan coils cover ground faster than concentric but at a loss of overall depth. A larger diameter coil will also cover ground faster while detecting deeper but it will find more larger-sized objects at the expense of smaller objects and a smaller diameter coil works the other way around.. You pay your money and take your choice.

So what about time spent searching. It has to be true that the more hours you put in, the more treasure you will find. But there are only 24 hours in the day and 168 hours in the week. You have to sleep sometime! Go out treasure hunting regularly if you can, this will keep you in practice and you will find more than if you go on a marathon session occasionally.

Let's look at search methods then. We'll assume you have a site to search, 69 yards wide by 70 yards long. That's roughly one acre. Buried in the site are five treasures within detection range, each marked with a cross.

You could do a systematic search with a metal detector, covering every square inch. If your overlapping search sweep averages 1.5 yards then you would need to cross the site 46 times and walk nearly two miles. It would take a few hours, however you would get 100% of the treasure finds.

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