16ga.com ~ View topic

Joined: 03 Sep 2014 Posts: 398 Location: Rochester, MN

16gaugeguy,

The firearms where I ended up polishing the chambers had rust and/or pitting.

I agree with everything you just stated.

But he plays one on tv .

Go ahead and polish your shotgun chambers. They do not work like rifle chambers. Many gunsmiths offer chamber polishing for shotgun chambers including Briley. Brownells sells a flex hone for polishing chambers.
Be it said, polishing the chamber is not a fix all for extraction problems. Worn extractor. Rim of the base not resized correctly. Complete base not being resized correctly.
Chamber should be checked for corrosion and checked with a caliper. Resizd hulls should be checked.
Worn extractors on an old gun causes a lot of problems.

I think some of us have a misunderstanding of terms here. Polishing a chamber is different than stoning or honing a chamber with a flex-hone or lapping it with a semi-coarse medium on a mandrel to remove reaming and machining marks.

Stoning or lapping leaves the chamber with a semi-smooth surface which allows a metallic case or hull base to feed well and also allows it to cling to the hull walls for a few micro-seconds when the cartridge is fired. A highly polished chamber allows the case or hull to slip backwards when the cartridge is fired. One is a good thing. The other is not.

Further, metallic cartridge cases and hull bases along with the plastic or paper hulls all cling to the chamber walls (or should) when the cartridge is fired (the metallic hull base must hold it's place or the plastic or paper hull will stretch and rip). They all act the same and serve the same purpose, I.E. to hold their place and contain the hot gases long enough for the bullet or shot column to leave the bore. There is no real difference in their function.

PS: In the past, I had a couple of 28 gauge WW compression formed hulls elongate due to overly high pressures. The load I was trying out was a mistake pure and simple. The plastic hull walls did not stretch backwards, because the hull bases held their place and were supported by the breech face. The plastic hull walls were extruded forwards towards the forcing cone under the firing forces. The hull mouths ended up looking quite lop sided. Needless to say, I did not fire anymore of these overly hot loads. I also thanked my lucky stars my Citori 28 gauge was stout enough to take the punishment without any damage to either of us. Lesson learned.

The shotguns I have vary quite a bit in measured chamber size. Used to keep the hulls separated for the different guns.
Wife and I went on a multi state hunt with 14 freshly loaded boxes of Non-Tox using my 'mixed' once fired hulls from all the different guns. 'Thought' I had the 9000 set up for a 'tight' chamber. Nope.
Got to the first and farthest destination and after an hour in the field the wife and I were back at the truck trial fitting all 14 boxes of shells to see which would fit in the guns. Had enough for the trip.
Now I size them all for the tightest chamber with a 'finger' style sizer before I run them through the loader.
That will not happen again.