mk70ss
I am reluctant to reply to your post but feel I need to mention some points to check. .....
I use to own this exact model and yes, it is an early issue as it has the wooden grips.
Check the following points and if you are happy with it's performance that that is what counts.....
1) Check the "clocking" on the front sight.
2) Check the timing.
3) Check the trigger pull as they have a reputation for being heavy.