New to the site. How do I fireform 30-06 shells?
Also I have some cases that have a ring at the base "swelled" the ring is .005 larger. Is this something to be concerned about? Can this be corrected? thanks

Iowaloha,

Fire forming is simply shooting a cartridge in a particular chamber. The internal presure will stretch the case to completely fill that particular chamber. It may or may not fit in another chamber.

Your description of that ring is a little vague. I would have some concern about it. It indicates an unsupported area in the chamber.

Your thread will likely get moved to another area in the forum.
No harm in that.
Welcome to the forum.
Cheezywan

Thanks for your help. The ring is about 1/4" above the base of the shell. I had one case rupture at this point. These cases have all been fired several times in the same gun. I normally only neckl resize. Also the base of the press touches the base of the neck die. I have been using 47.4 Gr of 4064 with 165 Gr bullet. Its almost like the shell is in the barrel except the last 1/4" of the base of the case.

H 196, can you post pictures? .005 doesn't seem like a lot, but that ruptured case worries me. How many times was it reloaded? Was the rupture right where the swelled portion is located?
Do you know a GOOD gunsmith? You could have a competent gunsmith check the chamber and the headspace.
How does the fired case compare to a new case.? How about length? Lots to look at. New gun? used gun? what is it's history?

There will normally be an enlarged ring just ahead of the cartridge base due to the case forming to the chamber size. If the chamber wasn't slightly larger than the cartridge OD dimensions, you'd have a hard time chambering the round and more so trying to extract it.

As far as the case separating at the ring, this may indicate an overly large chamber. The best method of determining this is to make a cast of the chamber with carrosafe and measuring the cast.

Assuming your head space is fine on your rifle, you most likely have your neck sizing die screwed in to far and your bumping your shoulder down to far causing a false head space problem that's why your cases are spliting just above the rim and it usully takes 2-3 firings before it splits on one side usully after the first firing you will see a line on the case as it splits from the inside out get a paper clip and bend it straight and use it to feel the inside of your case if it's starting to split you will feel it.

You need to back your NS die off then mark you case neck with a grease pen and check where your sizing too, you want to stop before it hits the shoulder neck sizing is only used to hold the bullet tight.

Fire forming is usully done when your necking down or up a case like 308 to say 260, or 30-06 to 338-06 in many cases I have used a shotshell powder like Blue Dot I don't recommend this for a novice reloader.

If your fire forming say 30-06 to your 30-06 chamber FL size so the bolt closes a little on the hard side using a normal load of powder, then next go round Neck Size most likely you will only get 3-4 NS loading before you will have to trim and full lenght size again.