If I may ask what kind of chemical solution was in the tank. Hope it isn't top secret.

the old barrel makers used to dip the barrels in a etching solution to match the barrels before they were assembled. i belive it was diluted hydrocloric acid. but that process did not last it was only for matching the tubes. i would like to know who first figured out how to do the black and white finish. very cool stuff at the testing lab. thanks for the look in.

I don't know the name of the solution. I asked and was told something that didn't make sense. He did say it was heated. I'll find out more and when I do I'll post it.

I knew ultrasonic would be great for barrel wall measurement. Just waiting for the technology to get a little cheaper.

Just for everyone's information lest you think I was smart enough to come up with this idea for getting my barrels tested on my own. The idea came from Edgar Spencer who passed it on to Jim Dispagno who relayed it to me. I want to thank both of those gents :)

Mike, I had all that testing capability in-house at my steel foundry. It was one of the reasons why I enjoyed staying after work; that and the machine shop. I had a Panametrics UT machine and 2 K-Bs. One of which would pay for a fairly decent A1-S. I Got certified in every NDT discipline, first as a level II, to do it, then as a Level III to teach it. "I liked it so much I bought the company" (Actually I hated the business, I just loved making steel and stainless steel)

Edgar, one test they wanted to run was to determine the composition of the barrels. Unfortunately that machine was down. I thought that would have been very interesting. Tomorrow morning I'm going to another aerospace company and have the separation welded by tig. I'll let you know how that goes if you're interested.

Mike, I would be interested in how you make out. The machine they would have used would have been either an optical-emission spectrometer, or an x-ray florescence spectrometer. The optical emission unit will leave a small (5/16" diameter) 'burned' area where a high energy source causes and arc, the emitted light is then broken down by a diffraction prism, then measured to determine each % quantity of each element the machine is set up for. You need to know this so they don't set it up to leave the arc mark in an exposed area. The x-ray florescence machine will not leave a mark. Not all labs have that machine, because of it's cost.
I'd want to know the chemistry before you have a welder pick his own filler material, so that you get a good weld, with regard to metallurgy, mechanical properties and cosmetics.

Thanks Edgar. Not being familiar with these things I would have never thought about that. I'll keep you posted.

Just got my barrela back from the TIG welder. Looks like they did a great job. Hopefully the next pic I post will be of the finished product!