What did john brown invent

John Brown invented the telescoping bolt, then integrating the bolt and barrel shroud into what is known as the pistol slide. Browning's telescoping bolt design is now found on nearly every modern semi-automatic pistol, as well as several modern fully automatic weapons.

Explanation:

I'm don't know which John brown you're talking about but I'm guessing this on. The one that I research was the one that started browning. Browning is a firearm and ammunition company.

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