I went on a deer hunt with some friends and family last weekend, and my brother had a bore scope so we started sticking it down barrels and seeing how good or bad they looked. I used it to check out my rem 700 sps varmint chambered in .308 that i use for target shooting and hunting and the barrel looked pretty rough. I have used this rifle for probably close to 3 years and maybe 1500 rounds. I used it for a lot of load development and it has seen many hot rounds, different bullets, dirt and weather. It looked like the throat was already pretty eroded and there were a lot of hairline cracks perpendicular to the rifling for the first few inches and then got lighter towards the muzzle. I also noticed there were many small patches of pitting or maybe porosity in the steel for the entire length of the barrel. The most interesting thing i noticed is that one of the rifling lands was quite a bit more worn than the others with more tool marks and more copper fouling. Now apart from all this the gun shoots fantastic. Im not a very good shot but i can shoot under a MOA with it regularly and sometimes under a 1/2 minute. The cold bore shot is usually spot on and it doesn't really walk much under heat. Has anyone else seen barrels behave like this before, and how much wear is pretty typical? Also when should this barrel be changed?