We have a beagle too that has a bit of a barking problem. The best option we found was a citronella collar. It does not hurt, but he doesn't like it at all. All we have to say is "Do you want your collar?" and he knows to stop barking. If he really can't resist, usually just showing it to him is enough to stop him. If he's really determined, we put it on and it works. Again, it does not hurt.....it deters. Lots of mixed opinions out there, but sometimes you just gotta do what you gotta do. I might add, we love our dog enormously......and tried the squirt bottle, advice from the vet, beans in tin cans, and anything else we heard before resorting to the citronella, which interestingly enough, was one of the first suggestions we were given by our vet. Had we tried it much, much earlier, it would have been better overall for him and he never would have developed a "problem" in the first place. I can't imagine loving this dog any more than we do, but we had to do what worked......just like any form of appropriate human discipline....
I am not going to get into right or wrong but we used one to get our beagle to learn quiet command. We zapped ourselves on the lowest number and it wasn't bad. We actually never had to shock her since the beep worked perfect. I believe it surprised her and she would look at us. We are fine with her barking to protect her domain but when we give the command quiet especially at o'dark thirty, we expect her to listen. We put it on her for about a week and everything was resolved in that amt of time. It was expensive but worth it. If the neighbors had complained, she could get in trouble.