Got to agree, find a trainer who is experienced in these collars. Search out a local retriever club and you'll likely find someone there.
I was on the way to ecollar training, working with a
neighbour who hunt tests and field trials. We were about to start into the conditioning. If you don't know what that means then you really, really need to find a trainer.
However I was able to scrap it as I found North/South fetching and worked it into a whistle recall. Yes, I have every confidence I can call my dog off of a porcupine a deer a turkey a snowmobile etc. But, I don't beleive there is 100% recall, since my dog is not a machine.
My dog is a Lab. I think you might search out some hound clubs for your beagle/coonhound. Recall is notoriously hard to teach with the hound breeds, it's just not what they were bred for. They were bred to follow their noses and it's hard to subvert years of honed genetics.