When trying to kill a bronto, get one normal bow, and about 50 arrows, and you should be good, the one thing is to run into a forest and every once a while shoot it until it starts catching up, then just keep running, also Spears come on handy
I was walking on the sand around my wood hut when i saw a male bronto. ON THE BEACH. I thought it was a diplo (i wanted a male diplo to mate with my female named Jenna, dont enen ask aboutJjenna.) I found out it was a bronto 😔.
Tip : Don't put wooden / metal spike walls near your base if you live in an area with a lot of sauropods.
this is why : since they like to wander around, There's a chance that they will get stabbed by the spikes when they wander near your base. And they will get mad at you, kill your tames, and wreck your base.
so please be careful and think twice before setting up spikes near your base.