Thread: Ammo splitting

Sorry if this is the wrong place to post.
We got a gun off a good friend. A Rossi 30-30. He said it’s only had 11 rounds through it.
Took it for a shoot tonight using Sellier and bellot ammo that came with it and they all split.
Is it likely just faulty weak ammo?
Anyone else had issues using sellier and bellot ammo?
We will run some different ammo through it tomorrow and see what happens.