I used to have a 442 and was concerned about firing +p's in it. I used a micrometer and dial caliper to measure all the pertinent areas of the pistol when it was new. Then I'd measure after every session, usually about 25 or 30 rounds, and record the results. Barrel/cylinder gap-backstrap thickness-frame length, etc. After about 200 rounds I quit measuring because nothing ever changed, not even a thousandth.