You say “fixed”. Hmm…. OK…. I still can’t follow what the issue was. Unclear why some snap cap dummy or ammo fit into chamber and some snap cap dummy’s didn’t. Makes no sense. To think that steel wool will remove a steel burr in the chamber seems a stretch to me. Barrel steel is tough and hard- much harder than steel wool, which is soft steel. It might remove a particle of something stuck on the chamber wall but actually abrade away a steel burr..?
A simple way to actually view the chamber of any firearm without having a bore scope is to use a simple thin mirror and bore light. I had some broken mirror pieces in the shop? Picked out a piece a couple inches long and about the width of a popsicle stick and epoxied it to a popsicle stick.
Put gun in cradle. Put bore light in muzzle. Hold mirror next to rear of chamber at angle so you can look into chamber along bore axis. Amazing how simple and how well this works for viewing a chamber.
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