I just found the same problem. For accuracy you need -.356,
.357, .358 depending on your barrel. Pull a couple of your bullets and see what they now measure. Over crimping may have you down to .352. All you will get is a leaded up barrel.
My new dies seem to be roll crimp, and the lead will spin in the case but will not push or pull. Seemed to shoot ok. be sure to use your barrel as a test gauge when checking . When I got to the range my test gun shot nice. My others seem to have tighter chambers. Not all the same. Damn Smith's, couldn't make'm all the same.
Mike.
Ps. you can swedge copper jacketed down also by over crimping.