I have a similar problem with a MK40 and KAHR Service was of no help.
I just purchased a MK40 Elite and I am very disappointed in the GUN and KAHR Service. I have previously owned three Glocks and I have never had a problem with them.
When I went to the range the first time, I fired 200 rounds to break in the gun, and three to four times, the slide stayed back, like the magazine was empty, but it was not. I pulled back on the slide and released it and the rest of the magazine fired fine.
I assumed this was just part of the breakin, but I went to the range yesterday, fired 100 rounds and the same thing happened two or three times.
I am using American Eagle ammunition, and I used the same ammunition on a Glock 23 and the Glock fired 100 out of 100 with no failures, on the samr range trip.
I purchased this gun for Self Defense, and it is not useful If I cannot depend on it.
I called Kahr Service, and they were not helpful at all, they said if it is is working 97% of the time, it is not the guns fault. How can that be! If I am using it for self defense it must work 100% of the time like my Glocks.
Kahr service refuses to do anything. I am suprised becasue I thought Kahr was a quality product, but obiously it is not and Kahr does not stand behind their guns.
Does anyone know what can cause this. I thought it might be due to a defective recoil spring but the Kahr Tech refused to do anyting, because it was working 97% of the time and he thought that was ok and not the recoil spring. I need a gun that I can count on, works 100% of the time if I am going to use it for self defense.
Kahr refused to do anyting!