Welcome to the sport! I love helping people with their 308s. As far as cleaning it stick to J.B. bore compound, it is kind of intimidating at first but it works excellent at keepin it clean and shooting good. Dont forget to use a powder solvent or sweets 7.62 solvent to clean out the compound. If somthing like sweets or the barnes solution is used, ram a double patch through after cleaning to ensure both the compound and the solvent are out all out of the barrel, that kind of solvent may damage your barrel if left in there long. As far as if the 308 is a good long range performer, it can be awesome! If I remeber right, your vs has a 26" barrel. If I am wrong let me know. If you have the 26" barrel, I think it has a 1-12" twist. Try loading the Sierra MK 168 and 175. If those dont work, try the 155 Palma match by Sierra. Powders? Try Hogdon VARGET for the 26" remington 308 for all 3 bullets. Also after shooting several 700 308 rifles, I found that they really like an OACL of 2.830" Even the 155. Also try RL-15 and RL-12 powders. And if none of those work well, try H-380. That yeilds High velocity, good accuracy and conscitent velocities. But VARGET seems to really work well in the 26" 308s with the 1-12 twists. Shooting. Watch how much shoulder preasure and cheek preasure you have. The butt should be felt but no preasure. The cheek may be felt, but no preasure. Stick to a clean rifle, develop a good load, watch the preasure and enjoy 2-4" at 600 yards.
If ever you have questions about the 700 308, email me anytime. firstname.lastname@example.org