So, i have finally decided to pull the trigger on a long time Wildcat i have been lusting over, the mighty 6.5/06 which is a necked down .30/06 case to 6.5mm! My reasons are many, mostly because the 6.5mm bullets are so darn good, and the large efficient case can push them at velocities the old 6.5s couldn't dream of. With modern barrel making and metallurgy, throat erosion should no longer be an issue, so, why not take advantage of what this ol' hotrod can do!?!?! I have the Highly desirable Doumoulin Mauser action and am working with my smith on a good barrel! Here is my issue, reloading dies! Redding and Lee both catalog full sets, and thats great, however, neither addresses( that I can find) case forming! I.e. expanding .25/06 Brass, or shrinking .270 or .30/06 brass, nor does it address if its possable to use the better MIL. Spec brass to form this chambering! So, I call upon the vastness of knolage here in the monkey tree to help answer some of these questions! Wish me luck!
I would have looked into availability of ammo, and reloading components, before I got the hots for a gun.
Heat,Not much of it like 120 degrees will turn the brass easier into what ever works for you,Like necking down the .06 case I would fill an old skillet with brass,throw it out in the sun for an hour,heat it up,bring it inside ,spray lube and the form the brass.
I've necked down used 30-06 brass to 6.5mm using 6.5x55 dies. I just made sure they were lubed and took my time. Yeah, I know the rim size on the Swede is slightly smaller than the '06 but they worked just fine in y Dad's old Mauser. A few got shoulder dents but most came out just perfect after a fair amount of case trimming. After I trimmed most I resized again and then did a final trim.
My oldest brother Larry and his buddy each bought 264 WM's in the early 60's. Those rifles were like laser beams. One year, I think I was 10, we were at the hunting camp and there was a squirrel on the hillside about a hundred yards away. His buddy decided to show us how accurate the rifle was and said he was going to shoot it. This is off hand shooting at a moving target and he used a tree for support. Somebody mentioned that it would be a hard shot. He said he was going to shoot it in the neck. A few seconds later he did just that the squirrels head and body separated. Larry hunted with his for 50 years and since he wasn't target shooting throat erosion never became a factor. It was literally one shot,one deer or elk, plus a few rounds to sight it in. I don't think a 6.5-06 would be very far behind in performance. Can't wait to see the pix!
I would think it wouldn't be too big a deal to run 25/06 brass over a .264 dia expander ball. I'd simply lube the inside of the case neck. There's only about .007" difference in the inside diameter of the case neck between the two. May want to clean the lube out of the case neck before you charge the case. Some lubes are petroleum based and can deactivate powder and primers. I'd use some kind of solvent that evaporates readily. Full length size in the 6.5 / 06 die and then trim to the proper length. The project sounds exciting.
Looks like both Die sets do the same tasks, with the Lee having the advantage of the 4th die for neck sizing down, and the expander for sizing up! I was doing my best Google-fu and came upon several sights where folks claimed to simply seat a boat tail in an un expanded .26/06 case, run it through the 6.5 die and go, and others say they simply run the .270 or .30/06 case through the sizing die and then trim to length! Most say the Mil brass is better and the case web will handle Mauser claws better, and capacity loss is so minor it's not worth worrying about! So far, so good!
'06 Mil brass might be getting a little scarce these days. In any case, check the date on the head stamp if it's once-fired because Mil ammo manufactured before about 1952 contained corrosive priming compounds and there will be residue present.
I can turn 30-06 brass into 8mm Mauser brass with no special gear. You should be able to run a 30-06 shell through the die and turn it into a 6.5mm. Trim if needed.
I doing think you need an annealing rig unless you are going to large scale manufactur ammo. Doing it buy hand with a torch has worked for for me.