I'm thinking of building a long range varmint rig good for out to 600-750 yd which is about as long as I'm going to be shooting for a long time, but must also be good for as close as 50-75yd. It will be mainly for prairie dogs and groundhogs and possibly yotes. I was wondering first off which caliber and secondly which bullet. I have heard nothing but good for VLD's and got some on order for my AR (70gr). Was going to make 2 seperate posts, but the bullet selection goes in hand with the caliber selection due to bullet weight restrictions. Going to be built on long action (-06 gun). Looking at the 6mmAI, 25-06, and 6.5-06AI. Trying to pick the caliber and bullet at same time to get the flattest shooting system, but also take into consideration barrel life. I know I have seen somewhere a 6mmAI shooting a small VMax @ 4000fps! I don't have a ton of money to rechamber every year so this option won't work for me. Was looking at a little heavier bullets for this. If I go with a VMax in 6.5 I can go with a 97gr VMax, but VLD's lightest one is 130's. So the heavier bullet has better BC but not nearly as flat. This will be a varmint gun only so heavier bullets not needed. So if I go with VMax's, 6.5-06AI might work. However, if wanting VLD's, then either 6mmAI or 25-06 since they have lighter VLD bullet selection. I've seen the VLD videos and read a lot on them and it seems that they need 2-3 inches to expand. Will these work on prairie dogs? I was shooting 75g Hornady BTHP's on prairie dogs and some of them didn't expand and they just went straight through them, and they crawled away to die. Will the VLD's perform similarly? If so, would you just stick with the VMax's or still shoot VLD's? If you have experience with these please let me know which you prefer and help me decide! Given these choices, which would you prefer for flattest shooting, but still relatively good barrel life that will take down varmints?