I have a DPMS LR-308 GII 24" Bull. I have had trouble with accuracy ever since I bought it. It came with a 6-18x50 Bushnell scope brand new in the box. I will fire two shots that are somewhat close to each other, but after my 3rd shot I will not hit the target. I notice the scattering of bullets. Is this a scope issue or a rifle issue? Any help/advice would be greatly appreciated!