What do you use to build your upper?

[centerfire]

Curious as to why?

I’m planning to use a Geissele reaction rod with my first build. I think this will be ideal for tightening the barrel nut as well as the muzzle device. When removing a muzzle device, the torque applied to the barrel extension would be in the same direction as needed to unscrew the barrel from the barrel extension, right? I would imagine the barrel extension torque would be close to 10x the muzzle device torque however. Has anyone ever had a problem unintentionally loosening the barrel extension in this scenario?

Torquing a muzzle device with the barrel mounted on a reaction rod runs the risk of damaging the pin in the barrel extension, damaging the receiver, or changing the index of the barrel in the barrel extension. The propper way to install a muzzle device is with a barrel vice.