Upper Assembly Questions

[montana]

I assume your talking about the prongs in the upper receiver?. Don't do it, it is not necessary as the prongs help center the tube. If you get your gas block aligned properly on the barrel your gas tube should fit the carrier key correctly. After assembly I will take my bolt out of the carrier and run it through my upper to see if there is any friction with the gas tube. Getting the gas tube correctly aligned will stop unnecessary wear on the gas tube button which could cause a gas seal problem. It will have no ill effect on accuracy. I will tweak the gas tube with a screw driver if it is needed.