40-50 cents a round is about as low as you'll find. And that will be online. Stores will start at 50 cents and go up.
UMC sells for $22/50rds. Online.
If you want inexpensive shoot something else. At those prices you can shoot 3 9mm or 2 .45 ACP for every .45GAP. You could trade in your gun for another I guess.
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