New AR15 build, 6.5 Grendel ???

[encorehunter]

The hand guard is your barrel nut. Your barrel nut is what holds your barrel in your upper securely. I've seen two off-brand hand guards in the last three years that had shit barrel nuts and the barrel was moving. It's a complete pain in the ass, but rebuild the upper with a different barrel nut and test it. I've tried to come up with a test to show how much a barrel nut is mating up with the barrel extension collar, but so far, it's just easier to rebuilt it with a reliable test hand guard and barrel nut.

This hand guard is actually seperate. The hand guard has 8 screws that attach it to the nut. Its going to the smith today. He believes it may be a crown issue, but he will go over it with me while Im there. Im sure he has several other hand guards as well, so I will be prepared to swap that out as well. Thank you for the help.

[SA Friday]

This hand guard is actually seperate. The hand guard has 8 screws that attach it to the nut. Its going to the smith today. He believes it may be a crown issue, but he will go over it with me while Im there. Im sure he has several other hand guards as well, so I will be prepared to swap that out as well. Thank you for the help.

the barrel nut is proprietary to the hand guard, short of a couple that use mil-spec like a couple Troy Handguards. It's only separate in respect that it can be dismantled. You use what they send with it, usually. Tell him to check it.