The 243 cases will fit fine from a standard FL die in my Mod 70. however I have a Sako Forrester and a Rem. 760 in which some will and some won't. In the 760 most that will, are still tight, and some still hang sometimes in the chamber 3/4 or so in.
The 25 cases I have issues with even after being FL sized will still not chamber in either of the 25's I have. The chamber they were fired in was reamed with a brand new reamer which was on the very outside of the specs, and they are belled out similar to the way some mil surp are after being fired in a machine gun. Even after FL sizing they spring back enough to hang up in the tighter chambers.
Here is a run down on the 25's expansion ring area sizes before and after sizing,
New case - .464"
Remington - fired .469", sized .467"
Ackley- new .465", fired .469", sized .468"
Others- fired .474", sized .470" (same die used on the Remington's cases)
As for the surplus cases, I learned long ago some will work, and some won't and the best thing is to just size them small to begin with and do away with the worry. I had some 308's loaded up for my Ruger Compact and when I hit the woods I found on the third shot into a pack of hogs, that the bolt would not close, not only that but I had shoved it hard enough trying, that I had to head to the barn and use a cleaning rod to help get the shell unstuck.
I am just asking to see if anyone knows of issue that might arise from this type sizing, since I already have the 308 SB die i figured I would give it a while, and I would hate to chunk the 25 cases if this won't work. They are hard enough to size in a FL die, as it is. I darn sure don't want them stuck inside my tight chamber on my custom rifle