After seeing our posts on the pin and weld issue that indicated that maybe ATF would no longer accept pinned and welded barrel extensions contributing to barrel length for NFA purposes, the NRA apparently went to ATF to get the problem corrected. One of my contacts at ILA just informed me that ATF has issued a corrected handbook, which states on the bottom of page 6:
The ATF procedure for measuring barrel length is to measure from the closed bolt (or breech-face) to the furthermost end of the barrel or permanently attached muzzle device. Permanent methods of attachment include full-fusion gas or electric steel-seam welding, high-temperature (1100°F) silver soldering, or blind pinning with the pin head welded over. Barrels are measured by inserting a dowel rod into the barrel until the rod stops against the bolt or breech-face. The rod is then marked at the furthermost end of the barrel or permanently attached muzzle device, withdrawn from the barrel, and measured.
So those of you with ARs that have 14.5 inch barrels with a 1.5 inch brake or flash suppressor pinned and welded on no longer have to worry they might be felons. Thanks to NRA for clearing this issue up.