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« on: July 20, 2010, 05:49:35 PM »
The 220 russian is a 22 caliber so I expand the neck first to 6mm. I don't use an expander ball in my full length die.
After expanding, I trim the necks for my 263 chamber. Then, I resize it with my normal full length die to get the proper neck tension so my bullet holds correctly, but I leave plenty of headspace.
I lube the case with resizing lube and make sure my case fits tightly ( when closing the bolt) in the chamber ( from shoulder to base) because I want the brass to expand laterally and not in length. The purpose for this is so you don't create a weak spot in the brass and a possibility for future case separation. I fire form all my brass and then measure the overall length of all the fired brass. It should not vary more than 3 thousands. I don't know what the max variation for other guys but thats what I use. For example, if a case has grown way more than all the others then you know it did not fire form properly and throw it away. So now, all my brass is fire formed and will now trim them to the exact length I want.
I have talked to other guys and they have found that when a case is not properly fire formed, it will continue to grow in length throughout many firing.
I have read the method in accurate shooter and trimming the necks twice for a crush fit is too much of a hassle for me. Also, the point of using a fire forming barrels is a good one. I would recommend though, that you own your own reamer. This means that your old barrels chamber is identical to your new barrels chamber.
Hope this helps. Fire forming seems complicated but once you get the hang of it its no problem.