I think the cylinder would need to be cut for the clips. Accuracy will suffer as the bore diameter is smaller for .45ACP. If you get into reloading, the price of ammo drops considerably.
if you must, there's no reason why you can't take 45 acp loads and stuff them into 45 colt cases- seems kind of silly, though- i just think it would be easier to "soft load" 45 colt- that would also save you some serious coin- i've found my 200 grain slugs and my 250's( both lead) go for the same buck, ( it's a few less by weight)so it's only the powder you would be saving on- the cases of course, are re-used, so 1000 will last you a lifetime with target loads-
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