9mm empty shell weird

jrcarbine

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I was shooting my jr carbine 9mm, then I noticed that all the empty shells had a odd primer strike. They all looked like outie belly buttons. The gun functions fine. I used blazer brass and sellier and bellot but still same results. Is this a bad thing?
 
If it's what I think it is, it can be caused by the firing pin retracting or being pushed back and the brass the primer is made from is extruded a little into the firing pin hole in the bolt face. Some say it's caused by high pressure but I've seen it most commonly in reduced pressure cast loads in rifles. Perhaps the specific powder, or the longer barrel of the JR, is causing a longer than normal pressure curve so the pressure remains elevated for a longer period of time; enough time for the hammer to bounce back and the firing pin to be able to be pushed back a little?

Does the JR firing mechanism press the firing pin forward past the bolt face while the hammer is down or is the firing pin free floating and the hammer just strikes it and retracts a little? I've not really noticed the "outie" primer indent in rifles where the firing pin is held forward when the bolt is uncocked but have in rifles with floating firing pins where the hammer isn't resting on the firing pin itself when uncocked.
 
If functions fine don't worry about it. Try different ammo if so desired. Each gun leaves its own distinct markings on casings after firing them. That's how cops figure out if gun was used in the crime, so pick up your brass.

Well I contacted just right carbines and addressed them of the issue, me and there gunsmith both thought it was the firing pin that was the issue, so they sent me a firing pin and spring free of charge. I put the new spring and firing pin in, but it didn't change a thing. There can be numerous things causing this to happen. The bolt face can be too short or the buffer spring might be too weak causing the bolt to come back earlier than it should.
 
Well I contacted just right carbines and addressed them of the issue, me and there gunsmith both thought it was the firing pin that was the issue, so they sent me a firing pin and spring free of charge. I put the new spring and firing pin in, but it didn't change a thing. There can be numerous things causing this to happen. The bolt face can be too short or the buffer spring might be too weak causing the bolt to come back earlier than it should.

Didnt you have an issue with overcharged hand loads that one pre detonated.. YOU sure it didnt cause damage?
 
By the sounds of it (pictures do help though), my carbine does the same thing.
My loads are within limits, there hasn't been any problems and the rifle functions fine so I'm not overly concerned about it.
 
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