I agree that the loop will never fall off and will outlast the rest of the gun.

"Both welds were laid in in a continuous pass, no back stepping or staggering, and both show strong undercutting- from the crowned appearance of the welds- were laid with 1/8" or 5/32' 7018 high iron deposition downhand rod- aka- "Rookie Rod"

Runs, why would anyone weld these barrels with either 1/8" or 5/32" rod on this thin of metal? The amps for 5/32" 7018 would be at least 200 amps.
Of anything 3/32", but more likely it was TIG.

David