I bought a stainless .22 Long Rifle cylinder and rented a reamer from 4D. It took about an hour to do the job. When the New Model Bearcats were introduced, a .22 Long Rifle/.22 Magnum cylinder convertible was an option. Ruger chose to do a recall and dropped the Magnum option.
Mine shoots just fine. Here is a hint: if you rent the reamer, rent the reamer handle at the same time. None of my handles fit the rented reamer.