500G:

Are you saying no solids {FMJ's} shouldn't be used at all?

Your previous post seemed to indicate the possible danger of using Woodleigh solids.

I know I have tried some "kitchen-table" experimenting; trying to resize .375 North Forks, Hornady steel FMJ and Barnes TSX down to 9.3 as I do with manyother bullets.

No dice on the Hornady FMJ and Barnes. They both seemed to take about equal amounts of grunting {technical term} to get them stuck in the die...

The North Fork went thru like corn thru a goose.

You are right about them at least in my experience, their ribbed surface resizes much easier.

My feeling on this subject is that there are severa TYPES of damage that may occur to a double. They may have a variety of causes, and certain bullets may cause one or more type of damage. Heckm even the mere shooting of MANY Woodleigh softs I suppose can wear out a barrel, just like any other rifle. Obviously you don't just spin the tube off and spin a new one on, so to speak, with a double like you do with a bolt gun.

As for "rifling" showing on the outside of the barrel, I have a couple theories, one of them related to bullets, one of them not. It is hard to imagine a slightly undersize bullet causing even spiral effect on the outside of the tube, but possibly other causes might. I have experienced a could similar phenomena occur in knifemaking.

450366 asks a VERY good question. Many combos have VERY thin rifle barrels. Anybody seen OSR on them?

400: Have you ever seen OSR appear on a newly blued barrel, or does it only show up on the original finish? Is the finish worn on OSR barrels?

As for the OSR: are the interior dimensions of the bores changed evenly? Have you slugged an "OSR" barrel before and after it occured?