18" barrel, and yeah the 90gr always cycled fine. I'm seeing similar markings with the lighter bullet load as well, so it may not be the load as much as the chamber and bolt on this gun itself. Both loads leave a nice little circle on the headstamp and the feedramps leave two drag marks on the bullet and neck of the case. I'm not seeing any primer flattening, but I am getting a bit of cratering with the lighter bullet compared to the load I was using with the 90gr