I got out to the range and shot my new KMK678GC today. Nice. I like it.
I shot it completely stock for a base line first. I have about 6-8 failure to fires or jams where the bullet gets caught on the feed ramp. Or it went into the chamber at too high of an angle and jammed. All of those happene in about the first 5 clips. I shot another 125 rounds with no jams of any kind, so I am assuming those were break in problems that got worked out. All 225 roungs were Federal Lightning.
After I shot 100 rounds, I put in the trigger shield. I have read that some people have had feeding problems after they installed the shield, but I didn't have any problems like that.
I thought I was having a problem with my sight, but only now, as I am thinking about it, I realized that I was adjusting the sight the wromg way. Guess I was thinking of archery where you adjust the front sight instead of the rear sight.
In any case, I was grouping about 2.5" to the left, and my rear sight was already all of the way to the left. I was wondering what was wrong with the stupid thing. But you move the rear sight the direction you want to move your group, right? So I need to move the sight right?
The other problem is the failure to extract live rounds thing. But now that I think about it, those were on those failure to fires. The lead probably got deformed, jamming the bullet in the chamber, preventing the chamber from closing completely and making it difficult to remove. There was no problem extracting live rounds that fed properly.
I am going shooting again on Friday and will see if any of the problems crop up again.