You can tell a lot of research went into the weapons part, I wished they added more to it and made it more complex. They have lathes and drill presses near some of the work benches, so I think they might have been toying with more ideas to expand on it. Like, add forging and casting, with all the scrap metal lying around that would have been perfect.
I found a site that has the feel of what I was looking for, http://www.weaponeer.net/forum/ they show you how to forge parts, make barrels, what metals to use, types of finishes, engraving, even gives links to official sites with parts, for real weapons, not homemade junk.
You can tell the devs have a love for that type of thing.
Do you think they'll expand on it in the next games? The Gun Runners could have used a little more depth at least.
Where do you think they got all of their information from?