I pulled this off a Swede site and the author seems to know what he is talking about. I'm a shooter, like Mikey and don't put much stock in what the disc says, only where the bullet goes.
James
Stock Discs for 1894 & 1896 Swedish Mausers
The most common of the bore discs. The range of numbers from 6.46 to 6.59mm refers to the diameter of the bore. The increments are very nearly spaced .0004" apart, or 4 ten-thousandths of an inch.
This disc is marked at 6.52mm. The pie-shape with 1-2-3 refers to the amount of -rust- observed in the bore, though I've never seen -rust- in the bore of a Swedish Mauser. This disc is marked a #1, which is better than #2. The Swedes had certain standards for acceptable wear in their rifles, but it's almost unheard of to see a Swede barrel that's worn out.
The lower section is mostly unused. "Torped" refers to the boat-tail 139gr m/41 bullet. "Overslag" refers to over shooting, and the "str" is abbreviated for streck. There are 6300 streck in a circle. One streck equals .1m at 100 meters. This is really an indication of how high a bullet will strike the target in relation to point-of-aim.
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I believe this to be an older style of bore disc than the one above. The bore dimentions are more limited, in this case from 6.49 to 6.55mm. This disc is also marked as a #1 condition. The "Torped Overslag" on this disc is marked -1-, indicating the bullet will strike .1m above point-of-aim at 100 meters. This particular disc is from a Husqvarna 96/38.
Some discs are seen without the 1-2-3 marked. These would be considered -like new- barrels and refered to as "zero" bore, or #0.