I took a tour of thier plant last summer, and I can swear that all of USFA parts are American made. Right down to the gun sock they are delivered in, and the box. I believe the only thing they did not do in house was barrels, but they are made in America. As an avid USFA and Colt collector and shooter, I was impressed to read recently that a very well known gunsmith was asked to refurbish an old 1st gen Colt back to its original configuration. It seems over the years it got changed in caliber and barrel length. The owner stated that the gunsmith used USFA parts to bring back the 1st gen Colt to original configuration and specs.
I love the idea that USFA is all American made, but I also do not think we should down play or ridicule the Italian gun makers. Along with Imperatto and Forgett, the Italians were instrumental in being able to bring back a true American legend to the market, the Colt SAA. I recently obtained an older US Patent FA SAA, and I was impressed. I like to use this idea when asked about Italian parts. There were many times in Sam Colt's career where his sales orders exceeded his production capabilities. He always and quickly relied on sub-contractors from anywhere, as long as the parts were made to Colt's specs. Those guns made with parts from somewhere else are still Colts.
With that said, I still have a fondness to the idea that USFA firearms are 100% American made, and I can honestly say they are!