Hi All,
As I said I have collet dies for several cartridges and yes high pressure is one reason for having to set the shoulders back but as this was when handloading for a .300 Win Mag in a Ruger No1B it was not a real problem, traded the rifle off so no longer load for the Win .300. I have not had to do so as yet in standard chamberings except 6.5x55 and I am loading for two different rifles in that so try to keep the brase seperate.
As for gettign lines down the necks??
cannot say I have ever noticed them but it sounds as the necks are on the thick side to me. When changing brass make or lot I carefully check for excessive pressure and adjust accordingly
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