No problem at all going from 7mm mag to 264 mag. That is all I use. Once fired Winchester 7mm Rem mag cases just run through a full length 264 Winchester die with one quick motion and you have a perfect 264 Winchester case. I use Hornady One Shot spray lube. I spray down the cases good and be sure to get some inside the neck and then give a little shot up in the die then LET IT DRY for about 10 minutes. Never had a stuck case or a wrinkle or dint. I then trim to 2.490 and remove the flash hole burr inside the case with my Lyman de-burr tool and then uniform the primer pockets with my Lyman tool. My super accurate load that I use for deer hunting is 66.5 grs Retumbo set off by CCI 250 primers and pushing a 130 gr Nosler Accubond 20 thousands off the lands an average of 3350 fps from my 27 3/4" Shilen barreled Rem 700. This load will shoot 1/4 MOA. These Accubonds fly better than their numbers say they will. I sight in 3" high at 100 yards and I am still 2" high at 300 yards. I just hold in the center of a deers shoulder out to 400 yards and it is BANG FLOP. These Accubonds are great bullets. Even as close as 50 yards they open up but hold together and keep on trucking. I have only recovered one bullet out of 7 deer killed. It was shot at 111 yards facing me with a slight left shoulder angel. I placed the bullet on the edge of the left shoulder and the buck fell on his butt and fell over dead as a stone. On cutting up the meat I discovered that the bullet had smashed the shoulder made soup of the vitals and was found against the ball socket in the right ham. It was a text book mushroom and weight was 87 grs. That bullet had to still be going at least 3100 fps and hit shoulder bone then travel around 4 1/2 feet of deer and held together and retained 2/3 of it's weight. That spells GREAT BULLET.
