[banddr2]

Here is a pic of a P99 on the left, and a G19 on the right. Notice the Glock muzzle is harder to clean

 

[banddr2]

Looking at your picture, if the P99 is on the left, that is definately rifling. I can even see that you have copper fouling on the high edges of the lands that needs to be removed, you wouldn't see that as easy on polygonal barrels.

 

[banddr2]

I know there isn't a huge difference in appearance, but on your pic I see two distinct orange lines outlining each rifling. This is from copper residue from you jacketed bullets. On the Glock .45 barrel I see mulitiple lines in the rifling showing more than just one land and one valley, but multiple levels from the highest point to the lowest point of rifling. You can see this in my previous picture also, except mine has no copper fouling. So IMHO your P99 barrel is rifled as it should be. Also, if you are ever able to recover bullets fired from each barrel you will see a big difference in the marks left on the bullets. I think a ballistics expert may say that it is harder to I.D. a gun with poly rifling since it doesn't leave as distinct a mark on the bullet as regular rifling does. Are there ballistics guys out there to back my statement up?