30-06 Rifle to .32 Cal Chamber Insert Barrel Adapter Reducer Sleeve - Oz Gun Mart
Could the use of 'adapters' which fit into the chamber and swapping of the bolt, extractor and other parts allow firearms to use different calibers as long as the new cartridge is
What are Shotgun Adapters? - Shotgun Adapters - https://chaszel.com
Caliber conversion sleeve - Wikipedia
these are shotgun adapters aka chamber reducers aka shotgun inserts and called by a few other names. they allow you to fire lower gauge (caliber) shotgun shells out of a larger bore
Auxiliary cartridges By any other name, still twice the fun - TheGunMag - The Official Gun Magazine of the Second Amendment FoundationTheGunMag – The Official Gun Magazine of the Second Amendment Foundation
20 Ga. Shotgun to 45LC Chamber Adapters
12GA to 357 Magnum & 38SPL RIFLED Shotgun Adapter - Chamber Reducer - Stainless | eBay