Der Ami;
Good comments there. Trying the bullet in the fired case is very good advice. I recall reading an article in the Rifleman many years ago on this subject. Seems a Gentleman had purchased a pre '68 model 70 Win whey they first became available in .243 Win. He had purchased a lot of 100 new brass for it. He had used this rifle for hunting deer, done a good amount of varmint shooting, Groundhogs mostly as I recall & a bit of informal range shooting. He had worked up a Conservative load & had reloaded these cases many, many times. A few had begun to develop split necks, so he decided to scrap the entire lot & start over.
He got the chance to buy a lot of National Match brass for the 7.62 Nato round (.308) which was, of course, the parent case for the .243.
Even though his load was conservative he dropped his powder charge by a grain or so & using the same bullets, loaded up some for trial. First few shots went well & then one round took the rifle apart. He sent it to the NRA for evaluation (I Doubt they would even do this service now) & they determined the brass in the necks had thickened in being sized down to where they were being wedged in to the chamber neck & could not expand so produced excessive pressure, this one was just more than the gun could stand.
That is indeed extremely good advice you gave to always check the fit of the bullet to be used in the neck of the fired brass prior to sizing it.
