"Loose" spot in barrel when cleaning

[kingmoochr]

Looking at another kit, but the seller mentioned the following:

***IMPORTANT*** just ran a patch down the barrel and there is a "loose" spot at the gas block, its hard to see and cant be felt on the outside but I dont know what it is or if it matters at all

Any idea what could have caused this or what it means? Does a barrel typically deform when bulged or could the gas block be hiding it? If so, is there any harm in continuing to use the barrel?

[bigboy]

Is it located right under the gas block? Could be the the gas port hole.

[Ryan in SD]

There should be no bulge, what sizes are we talking about here half a thou, 20 thou?

[kingmoochr]

Not sure, the kit is for sale, that blurb is all I know about it