How to assess the barrel condition

[happyhunter]

Gurus & Guides, I would like to know the methodology by which the barrel-condition of a gun/rifle is assesed/calculated (reffered to as %age of original/new.)
Any links available on forum? cheers. hh.

[MoA]

Without a borescope it is very difficult to asses the condition of a barrel.
However... clean the barrel with solvent, preferably about 5-7% ammonia, and look through it.
No pitting should be visible, the rifling clear and prominent.

Most calibers have an 'accurate' life of 1K-5K rounds... (.22lr excluded) . Then again accuracy is relative. To me it is sub MOA, preferably sub .5 MOA or .25 MOA. Many match shooters will swap barrels when accuracy drops from >.3MOA to anything over .3 MOA.

[nagarifle]

well even a new factory barrels are not perfect. That is polished or as its known hand lapped to bring the inside of the barrel to a mirror finish. yes without a bore scope it would be hard to see inside, a Dr. might have access to one for .22 the width should not be more then 5mm. failing that a light shone at one end might show some thing look for anything that does not resemble a mirror finish. ie scratches and rough rifling etc