The MK1 is pointier so it is more aerodynamically stable than the "onion" pod. You can compensate for this by flying really carefully though and do the gravity turn very gradually. This will be less efficient but at least it won't flip over so easily. It might help to somehow make the rocket longer as well, as it'll get a slimmer profile and the longer rocket body will act as a "sail" and counteract the drag of the pod.
Maybe post a screenshot of the rocket you're having trouble with?
Mjarf's post in KV-1 Onion pod, how to launch? was marked as the answer