I've been reloading .45 ACP brass for a few years on an RCBS carbide sizing die. But I've begun wondering why it's necessary, since the case is not necked down. My brass isn't deformed and I have never trimmed the case length. Since my decapper die is also my mouth expander die, wouldn't that also take any deformity out of the "tube" shape of the case if needed? Just curious to see what more experienced reloader think (it is a pretty labor intensive process on my single stage press to "size" cases that look the right size already). Thanks.