yes, the "new" models 22's after the mid 1970's had their "magnum" cylinder rollmarked around the outside..as for the numbers, they may have the last 3 digits, with or without some sort of "other" symbol or letter either on the front ( the usual spot) or they may be on the rear......these days, BOTH are usually marked, and at times only ONE of them, or just maybe ( and we have seen it also) NO markings at all, maybe they were in a hurry, maybe it was quitting time or Friday afternoon ,late..................do they time, lock up, on all 6 chambers??
if they fit and work , you can always mark them yourself with an electric pencil, or even a numeric hand stamp. That way you will always "know" which ones are YOURS and for THAT gun..........if your were here, I'd do it for you, won't be the first, NOR the last ones we will ever mark...... :roll: :wink: