The serial number on my .357 looks like it was stamped over on part of it. Can anyone tell me what the AJK means? its AJK88XX, but when looking at the serial number you can tell that the K is stamped over a 6. Can anybody help?

What does the AJK mean?, it means the serial number of the gun is AJKxxxx, proper for any S&W made from 1980 on. All S&Ws , except those with special or Performance Center serial numbers, bear SNs of 3 letters, 4 numerals.

You say that part of the SN is overstamped? On the butt, or in the yoke cut? In the yoke cut it is not unusual to see over-stamps, particularly the model number or -#. If it were on the butt, the "legal" serial number, it should have been cause for the frame to be scrapped as there is no way to distinguish between a "corrected" number and a tampered with/fraudulent one.

The number in the yoke cut is strictly for convenience when the gun is fitted with stocks that cover the butt number. It is not unknown to see this number mis-matched or corrected, even though really it should match the butt number.

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Gunsmithing since 1961

Welcome to the forum.
AJK is part of the serial number and tells us your gun comes from about 1985. In 1980 S&W started using the 3 letter serial numbers.
I don't know why it was stamped over a 6. Can you post a picture of it?