Darn good video! Your dad was not doing the worst job of cleaning, just about typical of his process. JB on a patch/worn brush will get all of that out, chemicals and patches will be a teaser at best..
You do have a great example to play around with your cleaning technique and document the process.
Barrels of this age normally show some pitting where moisture has got underneath the copper fouling, but it rarely is detrimental to accuracy since we are not talking about a target rifle.
The question is, what kind of barrel is it, and do you know the load your dad has been using over the years? Powder type often matters in the fouling build-up.
You do have a great example to play around with your cleaning technique and document the process.
Barrels of this age normally show some pitting where moisture has got underneath the copper fouling, but it rarely is detrimental to accuracy since we are not talking about a target rifle.
The question is, what kind of barrel is it, and do you know the load your dad has been using over the years? Powder type often matters in the fouling build-up.