IMHO and experience a 22 caliber reamer of good quality will ream quality chambers for hundreds of times.....IF you take care of the reamer. i.e.: clean the reamer every time it comes out, Use quality cutting oil and lots of it, never turn the reamer backwards, turn the reamer in the cutting direction even when withdrawing from the chamber, don't try to hog out the whole cut in one pass, use multiple ins, outs, cleans, re-oil chamber and reamer. Do all this enough and you develop muscle memory for the 'normal' effort it takes. When and if you feel the necessary effort go upwards it is time for a new reamer. Yes, the reamer can be reground, but it usually undersizes it. So, the solution is to just get a new reamer when the original has given its all. And store the reamer in a plastic tube container that never allows anything else made of steel to touch it.

Don't try to ream a chamber that has been chromed. I don't know anything about reaming titanium. I have reamed aluminum but only when using special cutting oil specifically for aluminum. ...............