I dont believe thier is any way to make a dog have shorter range, that is my answer to your question.
Range can be a difficult thing to breed for and I say that becuase a dog that was bred for short range can learn range thus throwing out some of the breeding traits. I think having the right amount of grit is the hardest thing to get right and maintain over a period of time. I beleive most dogs have too much or way to little grit. I hunt plotts and most people that I know prefer there plotts to be rougher than what I run. I dont want mine to be real rough for the same reason you posted. I dont want dogs with caught hogs being 1 mile away and it taking an hour to get there; I want them to bay thier buts off until I get there. Does it happens sometimes yes. I choose to have dogs with medium grit, long range and a lot of stick. I try to have dogs that are fast and I pair my dogs up based on speed so that I dont get slower dogs slung out
It sounds to me and I would recommend that you hunt the dogs the way you have been hunting them and try to enjoy them for what they are. Are they going to get killed on a hog, nobody knows and nobody wants that, but it happens. Try to get some pups that are like what you want and enjoy the dogs for what they are. If your catching good rank hogs than you are doing something right. Maybe you could consider a bay type vest that would help reduce injury.
Heck, I chased little pigs around a dang thicket halg the day yesterday and ended up with one lil pig. That sucks! anyway, long answer to such a short question.
Thanks for the response helped a lot