This is kind of a strange thread going from quesitons & comments concerning tight necked chamber to forming .270 Win brass from '06!
I have several tight neck chambered guns. First, a tight neck chamber is, as previously stated in the thread, a chamber with a neck dimension that is less than the minimum SAMI spec. Accordingly, it would be impossible to chamber a factory loaded round or factory brass into a tight necked chamber unless the so called tight necked chamber was not in reality a tight neck. A gun with a true tight necked chamber will be so marked on the receiver by the gunsmith that did the chambering - unless he was an idiot. To prep brass for a tight necked chamber you must use a neck turning tool that is really just a mini hand held lathe. Some machinest types have actually made some tooling so they can neck turn in a standard lathe. Neck turning is a slow process and constant measuring with a neck mic must be done to insure that you have 1 1/2 to 2 thousands clearance between the brass neck and the neck portion of the chamber. Accordingly, it would be a bad idea to try and use a tight necked gun for general hunting as a few grains of sand to prevent chambering. I don't believe tight neck chamber prolong case life since the necks are thinned and have a propensity to crack after repeated firings. Another thing that is necessary with a tight neck chamber is to body size and shoulder bump the cases about every five firings with neck sizing only in between. Don't get the thinking about case forming 06 to 270. Cant you still by 270? Why chance on overworking the brass and invite a case failure? Nuff Sed!