Hello, sorry if this has are ready been asked. I was wondering if a 8mm would make a good sniper/long range rifle? AS of right now, it looks like I will be shooting up to 300 yards. I was wondering what a good scope would be. I was looking at a mark 4. I think it is a3.5-10x 40 or something, not sure off the top of my head. Thanks for any advice.