Downbore pressures are substantially lower than breech pressures. Somewhere I have a copy of the famous DuPont pressure curve which shows that barrel pressures at 14" are about 500 psi and rapidly falling.
A barrel would have to be thin indeed to have problems with such pressures.
Someone else may have the pressure chart, or i can dig around and find it.
My take- if the barrel is otherwise sound, and you still have more than 10 thou thickness after striking the pits- go for it.
Remember, of course, that blackpowder pressures are EXACTLY like smokeless powder pressures. The barrel doesnt care how the pressure is achieved.
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."
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