I wish I had copied the the manual before I sent them back today. The picture in the MK7 manual looks just like the 53GR image. Even if my eyes decived me and it was only as far as you say, that is a small margin of error. That is a 0.65 centimeter difference from safe to catastrophic failure. J & G said they looked at 50-60 guns they had in stock, and did not see any others with damage. They also said that with the exception of one gun, all the others had serial numbers much larger that the two I received. If it turns out to be an isolated occurrence, I will be back, because the gun felt great. BTW my serial numbers were 1k-003## & 1k-003## one number apart in the 300's.