It looks like a small nic at the mouth of several cylinders.
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It looks like a small nic at the mouth of several cylinders.
Ok, got this cylinder in hand and found that there were some lava rock as I call them, rock hard carbon deposits in most of the chambers making it difficult to extract fired cases, and consequently difficult to load new ammo. It just needed a really good cleaning, it required the use of a reamer for a similar caliber which when turned lightly by hand scraped the carbon off the chamber walls without hurting the chambers. Throats pin out to .3145" and I suspect the previous owner didn't have much knowledge in maintaining his firearm, and likely sold it when it became difficult to load and shoot. Doh....
Should make a decent shooter with .314" boolits.
When a bronze brush turned in a drill motor won't remove this lava rock, that's what I call "hard carbon." A flex hone will shine it and skip right on over it. It takes a mechanical means such as a reamer, dremel tool with a steel brush, something metallic and sharp enough to dislodge the carbon but not harm the chamber is the only ways I know to get it out.
Yes I understand. I've never tried dealing with a revolver cylinder. In rifles it builds up at the end of the case mouth and the end of the neck in the chamber. A mild abrasive such as Losso or JB Bore Paste and plenty of elbow grease is the only way I've found thus far to remove it. I've been reluctant to use a chamber reamer as if you don't have the reamer that the chamber was initially cut with the fit won't be perfect, you might alter the headspace and as hard as that stuff is the reamer might very well get damaged.
I understand you're dealing with cartridges that headspace off the rim so different circumstances.
I got a .45 Uberti that had carbon stuck just ahead of the boolit. I soaked it is Hoppe’s #9 for a few days and chipped at it with nylon pick. Not as bad as the OP’s sample. I keep it clean, so the deposits have not returned.