Easy fix. Don' t shoot for groups with broadheads. Put several spots on your target and shoot each arrow at a seperate spot.

When I' m getting ready to hunt, I practice with the broadheads I' m actually going to be using. I want to know that each one will shoot where I point it. I use traditional style heads and just resharpen them before hitting the woods. If I used replaceable blade heads, each head would get a brand new set of blades before they go afield.