That explains it and it makes perfect sense, because that was the reason the doubles were factory chambered for 458 Win Mag durring the 1960s. There was a time when you couldn't sell a double rifle to anyone but a collector, because they were almost imposible to find componants to even hand load for them, especially in the USA. My first double rifle was a H&H cased double that I paid only $900 USD for because nobody had componants or ammo for it,so was a collector piece only, and double rifles were not a popular item in El Paso, Texas at that time!

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