I've fireformed 30/06 brass with cornmeal, 16 grains of Bullseye, and large pistol primers. Seemed to work fine. Any suggestions on the charge weight of Bullseye for .223 brass. What about primer choices for those cases. While I'm on the subject, what about for .308's. They are next.
Thanks for the help.

Not sure what you are asking... If you are wanting to fireform brass to a particular rifle, load to a few grains below max and shoot. It costs a bit, but I wouldn't try to extrapolate a "corn meal" load for .223. Ten grains of Unique and a standard rifle primer will work for the .308.

And I would think 16 grains of Bullseye in ANY case is too much, even if you are just shooting cornmeal!

Standard cases in standard chambers really don't need "fireforming" unless you are a benchrest shooter. True fireforming takes place whe one case in totally changed in configuration to another, such as a 7 US into a 7mm Bullberry or a .225 Winchester case necked to 6.5mm and then fireformed to 6.5mm JDJ.

And in those instances, what works the best is using a bullet that can be seated to the lands and a powder slow enough to give a compressed load but still fast enough to fully form the brass on the first firing. Such a scenario gives maximum support to the brass and doesn't allow unnecessary stretching -- at least not when one is talking about true fireforming.

The cream of wheat thing may sound good in theory but is certainly not the best for the brass. Additionally, it won't fully form the brass, either.

I've fireformed a lot, a lot. I think 10 gr. Bullseye is plenty & I use cornmeal only, haven't tried the cream of wheat since cornmeal works great for me. I tamp it down tightly, but not overhard.
Fill again, and tamp down until about 1/16 inch from top of neck. Then I put a drop of ordinary squeeze bottle wood glue & toothpick it around so it grips all sides of the mouth & makes a seal. Then let it dry, mostly overnight. I've formed
relatively extreme brass (like 11.15x58R Werdl from .348 Win. brass), nad have had no problems. I used to use W231 & 5-10 gr. & cornmeal. You don't have to go too high on the fast pistol powder, like I used to use mostly 5-6 gr. unless a big magnum case. Ordinary rifle primers are just fine, no need to get fussy about primers.
The cornmeal has no effect on the brass, just blow it out if any residue with canned air.
The only precautions...I once got into problems by fireforming a big overbore magnum case by not using enough powder charge...I used 5 gr. & should have used 10. You should try & balance the fireforming by not using too much powder, or not too little. 10 gr Bullseye will handle anything, I'd say.
Anyway, that's my input...
Best Regards,
Tom

I learned about cream of wheat here on AR a few years back.

I form 257 Roberts Ackley Improved cases from 257 Roberts cases with 10 to 15 gr of any pistol powder [red dot, bullseye, unique, etc] covered with cream of wheat.

a) If I can shoot straight up, that works.
b) At a range where I have to shoot horizontal, I shove the case neck in a bar of soap to seal the cream of wheat inside the case.

I tried about 100 combinations of fireforming.
I have given up on doing it in one step.
A high pressure single step forming makes my cases thin just behind the shoulder.
I put moly bore cream in the chamber as a lube between the case and the chamber.
Then I fireform with cream of wheat.
Then the case looks good, but not finished.
Then I load the case with a full rifle powder load and bullet, and get great groups.

Then the case looks finished.

tnekkcc-
Try the method I described. You'll no longer need 2 shots to get fireformed brass, and when done this way, there won't be thin or weak spots that plague brass formed via other methods.

15-8gr, on the ARs... bang, POP! formeed case, ready to trim.

jeffe

Thanks for the info everyone. Most informative. Am off and running.
stephen b.

quote:

Originally posted by Bobby Tomek:
tnekkcc-
Try the method I described. You'll no longer need 2 shots to get fireformed brass, and when done this way, there won't be thin or weak spots that plague brass formed via other methods.

That was the first of 100 things I tried.
I headspaced with a 257 Roberts reference.
I should have subtracted .004" for Ackley Improved.
The VZ24 Mauser firing pin can push harder than a bullet jammed in the lands PLUS the ring of contact between case and chamber where the neck and shoulder meet.

And a rifle that has done 5 shots .4moa does not get taken apart just to have .004" shaved off the shoulder and breech.