Originally Posted By eric10mm:


The polygonal rifling in a Glock barrel looks "worn out" compared to traditional land & groove rifling from Day 1 of its life. Glock's "polygonal" rifling differs from what most people consider polygonal rifling to be. In reality it is closer to land & groove style but with vastly different shaped cuts. Its rifling is also fairly shallow in comparison to traditional land & groove rifling. You can run some copper cleaner through your barrel but I doubt you'll get anything more substantial than a few blue patches for your effort. Some of the key features of polygonal rifling are reduced fouling and increased velocity due to less bullet drag and a better gas seal.

There are many Glock pistols who have fired in excess of 50,000 rounds and still exhibit acceptable accuracy. I seriously doubt your barrel is anywhere near being worn out.

Some light reading on the subject.
And some more.

For comparison's sake, take a look at any of the surplus C&R CZ82 9x18mm pistol barrels. They are true examples of polygonal rifling (as depicted in the right barrel view on the Wiki page shown above) and countless customers have complained to their dealer "hey, this barrel is worn out" when in fact it is not.