Hi my name is Tom Kudla (age 17) and I bought my first rifle (Savage 110 .270 WIN)about a month ago. I like to shoot at the range and shoot about 40 rounds a sitting. After a couple of shots my groups open up alot. It does not have the heavy barrel. Is this due to the heating up of the barrel? If so would adding a heavy barrel help at all? Thanks, Tom Kudla