Read this:
vzerone
Boolit Master Join DateDec 2015Posts338
Originally Posted by
geargnasher
I mean the concept of making a bullet that basically fits 90% into the throat eliminates all but one real full-diameter bearing band, the loss was by design.
What are you doing to deal with excess neck clearance?
Gear
Geargnasher I learned how to do it off the same two guys you tried to learn it from. You know who they are.
On you're bullet we're discussing here, I've see the diagram of it. Here's what I think. That's a long gas check shank. I assume it has a thin coat of lube on it from lubing/sizing. I don't see much contact from the bullet in the case neck, mainly the check at the rear and perhaps little of the bearing ban at the mouth. Contrary to many beliefs if that bullet does get bumped up it's not really happening until it's in the bore. I don't believe it's immediate in the throat. I see all kind of misalignment with that design and I also have to wonder how often the gas check comes off the bullet. Think about it. If it bumps up in the bore, the lube on that exposed portion of the shank keeps it from fully obturating and that gas check is all by itself on the back end.
**Maybe you three will be smart enough to understand it. It's post #127 in the thread How Much Force A Bullet Exerts Against The Rifling.