Hi Joe.I live in a known gold nugget producing area and done a few hours of prospecting with nil nuggets yet. Done all the regular self training with test gardens etc and probably spent about 60 hours testing myself and 705 on my own property. Both at home and attempted prospecting has to date produced lots of bullets and cases along with a fair amount of 100 year old mining junk, interesting but not nuggets! I honestly think it is very capable machine but I have not yet waved the 705 over a detectable piece at a suitable depth. (Interestingly I can hit a 2g lead piece buried at 10 inches but the 705 IDs it as -8, but rings up fine at up to 6 inches! Same after it has rained!) Most of the areas seem hard hit so I find myself looking in nearby areas without the signs of detectorists. I am confident one day I will find a little piece of gold, probably next to a bullet!
Also I have not noticed any real differences in detecting modes as far as depth goes. I usually use prospecting mode until I hit a junky area then stick with coin mode for the TID benefit, but don't ignore the low tones unless there is destroyed old tin fragments everywhere!
I would love to hear about how others have gone with nugget hunting and any tips to try, most here are into the coin and relic stuff which is great but Im more interested in the prospecting side of this great little 705.
Cheers and good luck with this fantastic hobby!