Building a rifle mostly for fire forming

[JohnO]

I already have two decent 6mmRAT uppers and a Krieger barreled bolt gun on the way. I would like to put together something just for fire forming brass rather than use the better rifles. I was thinking of getting a 6mm blank of medium to low cost and get it contoured for an AR15 upper that I already have. I already own the reamer. Any recommendations? I was thinking about a Shaw barrel, but the general feeling here is that they aren't worth the effort. I would gladly buy a good take off barrel that could be re contoured for an AR-15 20" service rifle if I could find one. I have spare lowers already as well.
Thanks, John

 

[Preacher]

As long as your only needing a barrel to fireform cases the quality of the barrel is nil...
More important is the ability to keep the FF barrel's chamber 100% the same as the regular barrel...