rob.ream258 said:
I'm quite sure this has been covered in the past but it's very hard to find by just digging through the many posts.
Using F75 purchased just prior to the DST model - not upgraded.
I've learned by trial and error & paying attention to the faint tone shift to determine the standard Bud Lite / Corona type of bottle caps while running in the various modes to include DE.
My question: Is there a mode / method / setting that you'll use to determine if the potential target is a non-standard type of cap? I'm having a huge issue with the aluminum screw off caps that were used on the old glass soda bottles and the size/shape of a current 2 liter plastic cap.
I'd love to know if anyone has cracked the code on this one and has the time to reply.
Thank you...
On most bottle caps and screw on caps using a DD coil on a Fisher unit I use this method and it works about 95-98% of the time.
I dug tons of these things getting confident in this, now I don't dig many at all and have confidence I am not missing much of anything good and the pic below is typical of some of the trash I come across at many of my garbage filled sites so I had to find a better way.
The wiggle and pull back or "Rimming" method.
Get a signal, these things will usually be in the dime to quarter range and sometimes pretty solid, swing that middle of the coil over them to get the most solid signal you can.
Many of these jump a lot from two directions because of how they are laying in the dirt so I usually avoid these and move on.
The ones that seen stable and coin like make short quick swipes keeping that target in the center line area of that coil and start pulling the coil backwards.
As the front rim of the coil passes over the cap there should be a drop in tones and numbers.
Sometimes from the 70's or 80's down to the 30's to 40's or so on the modern ones that aren't really rusted , most times into actual iron on the older ones that are steel and do rust.
No matter what there should be a drop and coins and rings don't do this but crown caps and screw on caps usually do.
Exceptions....some that are flattened and laying in the ground flat in relation to the top of the soil, some of the thicker "Big Mouth" beer caps or juice bottle caps that I think you mentioned can be pretty solid but those usually come in around a 68 or so and lower than a dime so another way to tell on these, some really old screw on caps from vintage salad dressing bottles can be more solid than modern versions and a few others.
Out of all of them the solid ones are rare and going into a pop top infested park and avoiding 95% of these things us a big victory in my book.
Keep on your toes, however...one time I got a classic signal like this and it wasn't a cap.
I got a jumpy high signal and I wiggled and pulled back and it dropped to iron as I passed the rim of the coil past the target...it was classic.
I should have moved on but something about the sound of that tone I heard, (I was using 4H at the time), made me reconsider but what it was exactly is hard to explain.
That tone was too nice, too sharp on the ends, too something that I heard that was a small component I do not hear in pop tops.
I dug this one and it was a copper wheatie and just south of where it was laying was a small rusty iron nail.
This is what caused that mixed jumpy signal and the classic pop top drop even though it was something different.
Other variationsto this method is using the side edge of the coil to rim these instead of the front or back edge and also swinging over these targets while raising the coil higher into the air which also usually triggers that large drop in tone and numbers.
We all get comfortable doing it one way or another and it is a fast efficient way to deal with these problem trash targets.
It is true you never know what you are swinging over until you dig it but in my infested sites I don't have the time, patience or energy to do that so avoidance is my preferred method.
If I miss something good, well..that's life...by spending my time digging more and better higher percentage solid targets the numbers say I should be more successful so I live with it, leave most caps in the dirt and the what if's don't bother me anymore.
