You are going to have to train them. They cannot be wild like that and your buck cannot bite you. That is completely not OK. I would start by clapping loudly and telling them "No!" in a stern voice. You can also squeal loudly when bit. Never hit or otherwise harm a rabbit when its misbehaving as they are prey animals. Even these big bunnies!
As for nail clipping and grooming. Here is what I do, I'm sure there are other methods but this is what works the best for me. I have trained my rabbits in the past and am currently working on training Pepper in proper handling. I follow the guidelines for showmanship. No. I do not show and will not show but the guidelines for showmanship of rabbits help you and your rabbit with grooming. You start by feeling the body, checking the ears and tail. At this time the rabbit should be sitting down calmly allowing you to examine it. You will check the rabbit's teeth and eyes then position her to turn her over. Once flipped on their back and you examine her under side, feet pads and privet areas. If you need to now would be the time to trim the nails. With as large as your rabbits will become you may need a second person to do the trimming but if your rabbits become well trained they will almost just lay there on their backs on their own making it easy.
At first your rabbits are going to be very unhappy with this but as they get use to you and the routine of the grooming check they will calm down and be fine with it. It is best to do this grooming check on a table with a towel or carpet square. Practice every day. Practice more often while they are still smaller and easily maneuverable.
Another thing, since your rabbits are going to be so large you will want to start researching clicker training and lead training. You want your rabbits to listen to you. To go back to their cage when asked and to not destroy stuff and preferably to come when they are called at a bare minimum. When training I use carrot circles or small chunks of apple, sometimes cilantro.
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Gandalf @
Rabbit_Lover @
RodentCuddles @stray_hares may have some other ideas. I've been out of the rabbit loop for awhile and training is something I can not remember as much as I'd like to. After having 3 kids somethings get pushed from your brain!
My rabbit Pepper responds well to voice cues and treats though. I have trained her to come when she is called, to stop peeing on my couch and bed (so gross Pepper...), to go home when she is told and to be groomed like I described above. My family is moving in 6 weeks to a larger house and at that time I will be working more on leash training her. I'd like to teach her to do rabbit agility since she is such a darn good jumper and super fast!