Carbon CZ

[Btrain]

Gents
I fall into the category of someone who bought a bore scope but has no real idea of what in seeing - picked it up after having some random ejection issues in a CZ 457. Is the black a carbon ring? Thought it too far forward to but but don’t know

Appreciate the thoughts

 

[KnowNothing256]

Ejection issues, or extraction issues? Carbon ring will possibly cause issues with extraction (case stays in the chamber), but not with ejection (case pulls out of the chamber but doesn’t fly out of the action).

My other suggestion with the borescope is to use the 90° mirror attachment, it’s typically much more informative.

Lastly, you can expect a carbon ring to start forming around 200 rounds. Opinions vary (widely), but a couple different schools of thought believe it negatively affects accuracy, esp on the first few rounds before the deposits warm up and soften. Use Boretech C4 on a patch to soak the chamber for 10 mins, give it a couple spins in the chamber, then scope it. You should see bare steel all the way into the lands.

 

[Btrain]

Sorry - Yes / extraction issues… 1 of ever 7-8 cases

 

[KnowNothing256]

Sorry - Yes / extraction issues… 1 of ever 7-8 cases

Ok, then yeah throw that attachment on the scope and post that pic. But, odds are it’s not the carbon ring.

What’s it look like under the extractor claws? Those spots get filthy depending on your ammo, a toothpick under the claws will knock that stuff out. If you’re still having issues after that, the next steps are to check the claw springs which requires some tear-down of the bolt.

 

[KnowNothing256]

Oh, and also clean the whole bolt face. None of that dark gray crud anywhere on the bolt face, get it all outta there.

I suppose while I’m thinking about it, also try to clean out the extractor relief cuts in the barrel breech face. A hit hard to get to those, but it can be done.