I have a weird hobby, which is that I like to collect failed gun designs. I have a number in my collection today that are functional, but considering that I don’t shoot them, I would be more than happy to get otherwise inoperable/non-functional versions of others that I would be unable to purchase in their functional form due to the strict gun laws in California and/or the military nature of the guns in question.
One gun of particular interest to me is the HK XM-8 rifle (Heckler & Koch XM8 - Wikipedia) that was cancelled. Obviously with the program being cancelled, they are not for sale, but hundreds or even thousands must have been produced for testing. Where did all those samples go? Obviously being an assault rifle, and a full-auto capable military one at that, I could not own one assuming I could find it. But what about the ones with warped barrels, or otherwise destroyed internal receiver parts that would make it inoperable (which may have occurred in stress testing?) Is there a way to get a cosmetically normal looking real gun that is otherwise non-functional. And before anyone suggests it, I am aware there is an airsoft version of the gun, but I am not interested in that.
I know some military guns are chopped up and sold in the US. They are technically imported for parts but a really skilled gunsmith can reassembled it.
The gunsmith on Sons of Guns reassembled a couple guns like that. Literally had to weld the pieces back together. Then they brought in a guy with a xray?? or some gadget that checked the barrel for any cracks and to verify the welds were good. I recall they had to reweld one of the of the welds.
I think these were AK’s and they did a bazooka one time.
My brother used to get a mail-order catalog from a company that sold reproductions of obsolete weapons that were inoperable. As I recall, they removed the firing pins and inserted steel rods to block the barrels. You could fill the magazine of an automatic, or the cylinder of a revolver, with fake cartridges, and work the action normally, but you could not fire anything from them.
A quick Google search on “replica firearms” turns up a number of companies that sell them.
Having worked at a military museum, we had a number of showpieces that had been rendered unoperable, usually that meant removing the firing pins/bolts and plugging the barrel.