Smithsonian item No. 222,349 – Keith Brown
❝ Guns outlive their designers, makers, and first users. When they retire from military service, they still have a lot of death in them.
I held the evidence of this in my hands in April, in the Gun Room of the military collection at the National Museum of American History. Thanks to helpful and knowledgeable curators, I was able to operate the loading and firing mechanism of item No. 222,349: a breech-loading Peabody-Martini rifle produced almost 150 years ago. It was in perfect working order.
❝ I thought back to that rifle when I heard in September that U.S. arms manufacturer Colt has suspended production of its AR-15 semi-automatic rifle. Some view Colt’s decision as a victory for gun-control activists, but it barely diminishes civilian consumer choice or access. There are already 16 million AR-15s in the United States and their modular design, and widely available and interchangeable parts, make them virtually immortal. Though the AR-15 owes its existence to Colt, it has done what military technology has done throughout history: It has escaped the control of its producers.
RTFA. Nice piece of history. Nice example of the postwar life of military firearms. In the instances of repatriated machine guns, they are usually “dewatted” – rendered incapable of rapid repeating fire. Enabling that function, again, after civilian sale, used to be called re-watting. BITD.
Eideard 
So, BITD…how easy was easy? Cost, time, etc.. Versus today?
Cheap and easy, BITD. Nowadays, dunno. Last gunsmith in the family died like a decade ago – or more. The wild and wooly, self-taught gunsmith I ran with in juvenile delinquent days died more years back further. Been outliving friends just like bad habits. Hope it balances out.
Colt has not really been a major player in AR-15s for some time.
Armalite sold the patents, licensing rights in Colt in 1959. Don’t think Colt ever sold ’em.
“In a series of stories, The Associated Press has detailed how the U.S. military has a problem with missing and stolen guns and explosives, and how some weapons have been used in domestic crime.
But the inside story of how two men who’d forged a deep bond amid the violence of the battlefield attempted to sell stolen Army weapons reveals another kind of threat: an organized group of soldiers and veterans taking advantage of flaws in the military’s system to make fast money.
This story is based on extensive interviews, text messages associated with a federal criminal case, private Facebook group messages, court records and documents from military investigative proceedings.” https://apnews.com/article/how-brothers-in-arms-plotted-theft-sale-of-us-army-weaponry-5fe1ad681d89dfc063c1d0d10b95b870