Wetsu,
I have rechambered and sporterized several Mausers, so I'm not a professional, I do have some experience. I believe it can be done. How much, don't have a clue. You are looking at some heavy machine shop work. You will need to alter the magazine box to accomodate the 1911 mags, the front part ofthe reciever may need to be opened up to accept the larger diameter chamber, or an existing chamber can be reamed out to accept the .45 acp round. You will need to shorten the barrel chamber on a stock or aftermarket barrel. It will still be cheaper than having a custom barrel made. Since the .45acp round is not a rimmed cartridge, you will need to do something to the extractor so it will catch the sent case. The bolt face will also need modifications. If I'm not mistaken, the base of the.45 cartridge is larger in diameter than the Mauser bolt face.
All this being said, it does sound do-able. Spend some time and think it out. You may want to make friends with a machinist to bounce questions off. Also, you could call a gunsmith in your town, make an appointment to talk with him about your project. Offer him his hourly rate for his time and his advise. More than likely, you'll get the advise for free. He will be hoping for the machine work.
Good luck and keep us posted!
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