View Full Version : case trimming and prep for 223 remington?

09-27-2008, 1:14 PM
I reload 223 remington for use in an AR for high power competition. I recently bought a used gracey case trimmer with the three blade carbide insert and a 1/4 HP motor, both of which I believe are upgradess, although I'm not exactly sure what the standard equipment is. To prep brass for the firtst time, beginning with once fired brass sorted by manufacturer, I wash with walnut shell media in a vibrating tumbler for about 2 hours, then I use a Lee full length sizing die with the deprimer installed on a single stage press. I then rewash in the media for about 20 minutes to remove the lube. I then trim all the cases in the gracey case trimmer, and then rewash for another 10 minutes to get out any trim shavings, etc., then load on a dillon 550.

When I first set up the case trimmer I found that if I inserted the case and did not turn ther was a large chamfer on the inside of the case in one location and exactly across from that there was a large chamfer on the outside of the case. If I turn the case all the way around I end up with a case end chamfer looking like the one in the first picture on this page
I figure this is from the cutter and the headspace indexer on the gracey not being exactly lined up, but I see no way to change it. Is this amount of chamfer detrimental to accuracy or case life?

I also have found that if I set up the average trim to length 1.750", out of every ten cases I'll have one at 1.745" and one at 1.755". I think that it is likely that this is because although all my once fired brass is coming from the same mfr, it's first fire was in multiple different rifles, some with looser chambers than others, and so even though I resize i with a full length die, the rim to headspace length is a little different.
I am wondering if the .010" tolerance is too much, and if so, would doing my first resizing with a small base die be a good solution? Will using a small base die cut down significantly the amount of firings I can get out of the brass?

I am also curious if anyone has thoughts as to whether it is a bad idea to was the brash with the primer removed, as opposed resizing before trimming with the decapper pin removed and then inserting a collet sizer/decapper in the first stage of the dillon.