I have a new Mossberg SSi One (single shot, break action) in 30-06. It shoots great groups, but has a problem that I am worried about.

I noticed that, even with factory ammo, it is extremely hard to break after firing. Also, the primer only has a very light dimple in the middle, but a pronounced ring around the dimple, which appears to be the firing pin hole. It sort of resembles a moon crater where the rim is raised higher than the surroundings. The primer also appears to be backing out. With handloads, it, many times, will not eject the case due to swelling (requiring a cleaning rod to dislodge the case).

Upon visible inspection, there is a gap between the reciever and the barrel. I assume that this is the root of my problem -- the primer sits way out from the firing pin and, upon detonation, the case slams back on the receiver, causing the rifle to be hard to break and forming the primer anomolies I described.

I have e-mailed Mossberg, but have yet to receive a reply.

What do you guys think?

I`d quit firing the rifle untill I had it inspected and repaired. It sounds like a head space problem and could be/IS dangerous if true. I would give the manufacture another call or take it back to the shop that sold it to you.
There should be NO gap between the case head and the reciever face.

OL'JOE IS CORRECT. STOP FIRING IT NOW! YOUR HEAD SPACE IS BAD AND IT COULD BE FROM A METALLURGY PROBLEM AND NOT A MACHINING PROBLEM. IF IT IS A METALLURGY PROBLEM YOUR HEADSPACE COULD CONTINUE TO STRETCH UNTIL IT SHEARS. BAD NEWS....
I HOPE THIS HELPS

Mossberg has asked me to return the rifle to them along with some fired cases.

They are even paying for shipping.

I'll report the results.

I suspect your headspace is OK,,,,What is happening if I understand your description is the primer is flowing into the fireing pin hole and when you open it then it shrears off the flow...You need to send it back to the factory or have a gunsmith bush the firing pin hole...

Ray,

I think you pinned down the problem. That is exactly what appears to be happening.

The gun is on the way back to New Haven as we speak.

Man, has my luck with new rifles sucked this year! This makes three in a row with a problem.