Here is how I make .284 brass from 6.5 x 284.
1.) Run the 6.5 x 284 brass into your mandrel die. Back off the handle, lowering the ram, turn the case about 1/3rd turn and run it back up into the mandrel die. Do this about 3-4 times and you will feel the brass eventually go in nice and smooth. Now you KNOW you have moved all the imperfections to the OUTSIDE of the case neck wall.
2.) In your case, with a .317 neck, turn off about a shade over 1 thousandths to clean up the neck about 90 pct. At this time, you can inside and outside chamfer the case mouth.
3.) Anneal that NEW brass.
4.) Now run the brass back into the mandrel again, doing the same turn deal a time or 2.
5.) Thoroughly brush out the case neck
6.) Prime the brass
7.) NOW take a Q-Tip swab and swab out the inside of the case neck with Imperial Dry Neck Lube.
8.) Charge the case with powder and seat the bullet.
This has worked so well for me, that using this method I have found that the "Virgin" brass you just made will shoot just as well as fireformed brass. I have used it in BIG, as in State Championship Matches and cleaned the targets with excellent "X" counts.