Tyres hit out

Hello together, I have a problem at the moment that I have never experienced before in this way: I bought my BWM last December, there were logically winter tires on it, the summer tires incl. original BMW Alus got so to it and had them stored in the workshop of my trust. As far as unspectacular. Car runs super and supple as it is heard. Today I decided to let the aluminiums with the summer tires finally pull on it incl. Au When I was driving the first 100 m, I thought I was hit by the blow. The tires slag back and forth that it is no longer sacred. With every small unevenness/gulli/sinked curb, it rips the steering wheel almost out of my hand. I don’t mean the trembling that you sometimes know at higher speeds, that I already had with other cars, that’s something quite different. So again, with both hands clamped on the steering wheel, back to the workshop. n checked, unbalance weights checked, rims inspected, but all good. Colleagues there for fun again made winter tires on it, I drove around the block, cart runs perfectly, like on rails. So problem is definitely the tires / rims. No solution found, no idea, now I’m hopping here, with a BMW, which can only be steered by the road conditions and not by me. How can such a thing be??? Summer tires are still good, not 3 years old, profile absolutely Is around 225/45 R17 Continental. The winter tyres that ran well were Hankook 195/65 R15. I don’t really have a chance to get new tyres and rims for a four-digit amount… Has one of you ever experienced such a thing??? I would be really grateful for ideas…