Gas block rail on ar15
Ok I have a bushmaster v-match ar. It's the flat top a hand no front rail. I got a quad rail gas block. Finally got it on. Pain in the ass I tell ya. But my question is (and I've looked elsewhere) how to match the hole in the gas block up with the hole in the barrel. I read its just an eyeing type thing. I butted the block up against the thicker barrel diameter under the free float hand guard. And lined it up from side to side as close as I could. I know the gas block hole is much bigger than the barrel hole too. What can I expect if it doesn't match up?