IMO,it makes a difference where you are welding and with what.
If you read Kreiger's barrel making process,its apparent that stress relief is a major part of what you are buying.That is gone if you weld on the barrel.
I'd never accept welding longitudally on a front receiver ring,even tig,such as a scope base.
Bolt handles? There is a way to screw a heat sink/thread support into the bolt body before welding.I added a gravity flow tube to the heat sink so it and the bolt body were water cooled while the weld area was dry.It worked well.No heat color to the cocking cam.
I have an STI TruBore 1911 comped barrel that has never been in a gun.Unfortunately,somewhere in its history the hood became .3675 wide.My slide hood notch is .375. IMO,.0075 is too much clearance. I got the barrel cheap,but I have a problem.
I found a nearby source for this laser microwelding.I have had it done to molds before.This barrel is .416R. In the video,the filler is 420.Note the welder's bare fingers are in contact with the workpiece.
I'm thinking I can get my .004 on each side of the hood.
I'm not building it to sell,its just a way I can afford to build myself comped double stack 38 super...just because. Please watch the video before commenting.This is far from goose pooping 6013 on with the buzz box.
https://youtu.be/K3mFAyq3UAk
I am wondering about narrowing the notch in the slide instead.I'll probably talk with the welder.