I know there's threads out there about ballistics out of 11.5" SBR's, but I couldn't find anything specific to the KAC 11.5" Upper. I found a good deal on some Federal Lake City 55 gr 5.56. Is there any reason this ammo wouldn't be a good choice for the KAC 11.5" Upper? I am about to put together a pistol, and the upper will be brand new. Is there anything else I should consider for breaking it in?