A sign of a warped carrier is that it comes loose from the ram or the zero adjust no longer works. The carrier is cantilevered from the ram something like a diving board. If you misadjust a rear die to touch the shell plate, you will put thousands of pounds of pressure on the carrier and will bend the casting.
The bent casting will distort the hole where the ratchet gear fits rendering the index mechanism non-adjustable.
The front die (sizing die) can and should be adjusted to stop against the shell plate. By stopping against the shell plate, you will assure the shell plate rises to the same point every time making the most accurate and consistent ammo.
Per our Lee Lifetime Guarantee, we can offer a 50% discount on a new reloading press. To take advantage of this offer, please send us a photo of the existing Lee Precision product you own, with a photo ID or piece of mail showing your name and address in the same photo. Also mention what product you would like to upgrade to.