Fixed: 18" Alexander Arms barrel: 2.5+ MOA

[Herzo]

I'm no gunsmith, but I'd think the opposite would be easier: take the pre-pinned extension, torque it onto the raw barrel, then, using the pin and the extension, mount the raw barrel into a drill rig and drill the gas port.

In the case of my barrel, I'm curious if plugging the existing port is possible (heat, stress, intrusion into bore), and then simply re-drilling a new port would not be possible? (I'd assume the old port would intersect with the new one, so drilling through the plug would be necessary. The biggest issue would be the effect of plugging the port would have on the barrel.

A number of years ago, I had an over gassing problem with my first carbine build. After determining that the gas port was substantially over sized, I drilled and tapped the gas port for a #8-32 , being careful to leave the hole 1/8" short of the bore. I then installed a stainless set screw in the hole and drilled the screw for the proper diameter. After that, I filled the screw to match the od of the gas plug journal. Problem solved.