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—”They didn’t develop it... It too conveniently fits our barrels and bolts.”
Parts is parts!
IMO, the glass is the hard part.
This reminds me of the Toyota Land Cruiser back in the day. The engine castings were an exact knock off of the Chevy 235 inline 6. We probably sold them the casting molds. The only difference was the holes were tapped for metric bolts.
They didn’t design or develop that engine. We did... And we already had tons of them before they “introduced” these engines.
Not to mention the ballistics computer (https://www.americanrifleman.org/content/ballistic-software-for-long-range-shooting/)