I have an early K9, carbon steel, probably circa '97. The two magazines that came with it are simply labeled "Kahr". I bought some labeled "Kahr 9-7" which fit, but require, even unloaded, some extra pressure to lock into place. I also bought some "Kahr 9-8" magazines and some spacer base plates. I cannot get those to lock into place.

Any insights would be helpful. Is this due to spring tension? Is there a difference in the design of the magazine that make them either harder or impossible to lock in place?