I tried it...ONCE! I had a .400 Cor-Bon barrel for my Springfield Armory 1911A1 GI. I just never, never, could get that thing to load right. It had constant failures to feed. Now it may be that I just got a bad cheap barrel. But I DID have a gunsmith put it on. It would have multiple failures to feed, I would take it back to him, he would find nothing wrong. I would shoot it again and experience the same problems. .45 ACP brass was easily converted to .400, just necked it down. I finally gave it up as a bad job and sold the barrel and the dies to a different board member that thought he could fix the problem. He never posted me back he couldn't, so maybe he did get it to feed. Anyways I finally just bought a 10mm. I liked it so much I now own two others and a Mechtech CCU to make one of them a carbine.
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