Someone said it quite well...

A bulge is just a reverse dent. Bulges are reduced by careful and judicious peening all the time. Check for a crack, have a knowledegable barrel man work on it, and get on with the program. Or shoot it as is. Or get it tubed. All viable options.
Another would be to get the damaged barrel sleeved.

At 15", the pressure is in the neighborhood of 4500 psi and some change, extrapolating based on the Dupont curve.

Kirk Merrington can do it, or Mike Orlen.

Regards

GKT

Texas Declaration of Independence 1836 -The Indictment against the dictatorship, Para.16:"It has demanded us to deliver up our arms, which are essential to our defence, the rightful property of freemen, and formidable only to tyrannical governments."