This is a very very subjective area.  In the realm of buying and selling, a gun dealer is likely to describe a bore differently than a buyer would.  Some people use a one to ten scale, which is of course subjective as well.  I always like how austinsguns (gunbroker) describes his guns.  He provides a numerical rating and then describes exactly what he sees (e.g. pitting, frosting, strength of rifling, what’s between the lands).  I’ve looked through a lot of dealer’s catalogs over the past 45+ years.  As a generality, I see the majority of the bores are either described as, “excellent” or, “very good.”  One collector friend commented, “very good” means, “you can see daylight.”  But seriously, if you look though a catalog of vintage and antique Winchesters and see the majority are described as, “excellent” you know that isn’t true for all of them.  

Mike and others, as has already been said, this is indeed very subjective and depends on the eye of the beholder and their interest in the rifle as either seller or buyer.  To add yet another dimension, most are described by looking in the muzzle with some sort of light shown in the breach.  The new, blue/white lights tend to burn out my vision in this regard, and for this I prefer a yellowish maglite shown indirectly.  That way you can see the pits better, shadows of unwanted characteristics, etc.  Or if you have a good heart, try using a bore scope!  The 20 power magnification will take what seemed to be a smooth, shiny barrel that would compete with a newly made rifle and turn it into a sewer pipe!  That might happen with today’s newly made rifle as well, so it pays to be experienced and having looked into a lot of barrels with one before judging an original Winchester of some vintage.  Frosting, in my personal opinion, is a dull looking but silvery finish to the bore that is indeed caused by the beginnings of generally evenly distributed small pits and uneven surfaces.  Hope this helps some.  If in doubt, refer again to the passage about whether the person is a buyer or a seller!  My opinion for what it is worth.  Tim

Bill Hockett said

I think especially for black powder era guns it is possible to have a bore condition that does not necessarily match the outside condition of the gun.  I have a theory for why this might be.  Winchester and other cartridge manufacturers loaded black power rounds up into the late 1930’s in some cases.  For some of these cartridges (such as the .40-60 WCF) black powder was the only load, at least by Winchester.

“Little Johnny” may have been able to borrow grandfather’s rifle and the black powder cartridges that went with it.  After shooting it, he wipes it down and puts it back in the closet or gun cabinet but does not clean the bore.  It stays that way for years, the bore turning into a sewer pipe, but the outside aging more gracefully.
   

I’m sure you’re right about that being how it often happens–the original owner, & maybe subsequent ones too, cleaned the bore conscientiously, then along comes some dumb-ass (not necessarily a kid!), fires a few shots, maybe only one, but doesn’t worry about cleaning & the damage is done.  Not to be forgotten is that cleaning a BP gun from the muzzle with hot water is a messy chore, so nobody inclined to laziness is going to do a good job. 

TR said
 It’s hard to find a 73 in 32-20 and 22 that have a good bore. Perhaps it’s because they didn’t have rods in the butt or the small bore was harder to clean. Black powder and corrosive primers can quickly down grade the bore if not cleaned after use. “Little Johnny” or any non firearms savvy person could also do it. T/R  

Tom I also think these smaller caliber guns, like shotguns, just got used more than the big bore guns.  We are overlooking another important aspect.  Primers up to and including WWII had very corrosive primers.

I don’t like any artificial light in the bore when I inspect it. I use reflected light.  As long as a black powder barrel has no Major pits and still has a good amount of rifling I believe it will shoot.  Some collectors get too hung up on barrel condition especially the ones who never intend to shoot it anyway.

Another factor that hasn’t been mentioned: rings or bulges.  It’s one thing to buy a rifle sight-unseen that has more pitting than was expected, but for me, it’s a whole different world if there is a ring or a bulge.  I know it goes without saying, that should always be mentioned.  But it isn’t always.  I find it amusing that much of the time, when a ring or bulge is mentioned, it is followed by, “but still should shoot fine.”

Chuck said

Some collectors get too hung up on barrel condition especially the ones who never intend to shoot it anyway.  

So true.  It’s just a factor to consider in appraising value. 

steve004 said

Even if you never plan to shoot the rifle, a poor bore can certainly raise its head when it comes time to sell.  

Well, of course…but if you bought the gun at a price that fairly reflected the bad bore, you shouldn’t expect to get top dollar when you sell.  There are always folks like me who have to settle for what they can afford to buy, & that may mean compromising on the bore.

Seriously, how many of you collectors that only show your guns have had a friend pick up one of your guns and even look at the bore?  Most of my friends don’t know what they are looking at on the outside let alone on the inside. If it’s pretty they like it.