Dan, Ammo is ammo. Get some 45 ACP 230 gr full metal jacket FMJ round nose you'll be just fine. No such specialty ammo as "break in" ammo. Just the stuff you would use at the range.

230gr factory ball (round nose FMJ) ammo.

any quality 230 grain Ball (coper jacketed round nose ) ammo get it by whichever manufacturer you can find now the 230 grain ball is what is important as that is what the 45 acp was made to function with

Dan, any factory new 230gr FMJ and what ever ammunition you will be using for defensive ammo will work. Break in with the target load and then check for reliability with your defensive load. budsgunshop.com/product_info.php/products_id/26371/cci+3480+blazer+45+automatic+colt+pistol+%28acp%29+230+gr+total+metal+jacket+50+bx%2f