Well there's the fact that you referred to the barrel blank as a "tube", too smile I know that you were just trying to keep it simple, but apparently Gonhuntinnow is a nitpicker of the highest order. Maybe he doesn't think Oly arms uses a pulled broach either, based on his use of bold characters? But he'd be wrong, as:
Quote
Broaching gun-barrel bores necessitates a rifling broach. This special tool is very long so it can traverse the barrel�s full length. It has relatively few teeth, as barrel grooves are only a few thousandths of an inch deep. The broaching machine pulls (emphasis added) the broach through the bore while simultaneously rotating it to produce the spiral pattern

Source: http://www.ohiobroach.com/index/broaching2



Personally, since he's so keen on your bona fides, I'd not bother to respond to him until he's disclosed his own background.