Have a wonderful 20 gauge shotgun from Suhl made in 1925...just a wand...in very good condition except for a deep pit on the outside of the left barrel which someone filled with soft solder. My question...is it feasible to remove the solder and micro tig the pit? I understand that when reblued, the repair will not match. But will the barrel have more integrity. I have shot low brass loads without issue.

Yes, and the Micro part is not necessary; TIG is very precise. It will likely match when blued. More integrity; possibly. Where is the pit? German shotguns have to undergo some very strenuous proofing.
Your problem will be to find someone who will actually weld on a barrel.

It's doable.

https://microarcwelding.com/services/

Also, you might contact ted thorn. He's a member/poster here.

I've used Restorative Welding/Peter NAgle in the past.
Excellent results and fast turnaround
http://restorativewelding.com/...welding/Welcome.html
Never had bbl welding done, but other gun parts welded.

I've had others recommend Micro Precision Welding.
But I have never had the occasion to use them.
https://www.microprecisionwelding.com/


If the pit (pitting) is at the breech end of the bbl, the thicker area of the tube, some engravers can inlay a piece of steel into the area and polish it flush. Once rust blued over it will 'disappear'.
Not all engravers do that sort of work of course.
It avoids welding which can bring up all sorts of bad thoughts when combined with the word firearm.
The inlayed piece is no deeper or damaging than a deep relief engraving cut had the bbl's been engraved at the breech.

Either way, the repair would need to be file and polished flush. The area polish matched to the surrounding finish and then rust blued to match.



updated,,first link fixed 8pm 11/8

Tig and micro TiG cause heat and change the structure of the parent metal....there's no way around it.

We TiG and Micro TiG but have switched to a better method.

Micro pulse fusion TiG puts the smallest beads possible with almost zero residual heat.