Fireforming cases with COW

[Blackwater]

A friend wants me to help him form some Ackleyized cases, and I plan on using cream of wheat. Just to make sure I get it right, how much Unique should I use in a .260 Ackley Rem? I'm thinking about 10 gr.?? He doesn't shoot cast yet, but I think I can get him started when he gets rolling. He's as cheap as I am, and the allure of cheap and very satisfactory ammo will be VERY appealing to him. He just hasn't yet realized how effective and useful they can be ..... but I plan to teach him.

I'll be lubing the cases with Lee water soluable sizing lube so the shoulder can slide out properly.

[fredj338]

A friend wants me to help him form some Ackleyized cases, and I plan on using cream of wheat. Just to make sure I get it right, how much Unique should I use in a .260 Ackley Rem? I'm thinking about 10 gr.?? He doesn't shoot cast yet, but I think I can get him started when he gets rolling. He's as cheap as I am, and the allure of cheap and very satisfactory ammo will be VERY appealing to him. He just hasn't yet realized how effective and useful they can be ..... but I plan to teach him.

I'll be lubing the cases with Lee water soluable sizing lube so the shoulder can slide out properly.
I also shoot a 260ai but find you really don't need to fireform, the 260 cases can be fired fine in the ai chamber, that is kind of the point of the AI. Accuracy is quite good but of course better w/ formed cases. FWIW, you NEVER want to have any kind of lube on the cases during firing, never. The shoulder will form fine.
I have used COW & pistol powder to fireform some 375RUM brass to 404 jeffery, just to do it. No need w/ the 260, I just load up some 260 rated ammo & go target shoot. Here is a good article on fireforming. http://www.6mmbr.com/260AIforming.html

[HangFireW8]

I tried it all with .257AI 40 degree, mine was a bit difficult because it had a tight neck- which made case forming harder than most.

The problem with using pistol powders is that they are so fast, they can blow the shoulder forward drawing from the base of the cartridge, and leave a thin ring midway- the infamous incipient case head separation.

My final solution- neck up to the next largest caliber, then size the neck back down to the correct caliber, but only long enough to barely chamber- the case now headspaces on the bump on the neck. Then, a full charge of 4895 and a jacketed bullet, because cast doesn't generate pressure fast enough early on.

And yes, I lubed the top 1/3 of the cartridge, every single one, and if I didn't I would often find that thin ring of incipient headspace separation. After shooting I'd carefully clean out the chamber with a degreaser. The hazard of oiling cases is that it increases bolt thrust. The upside is that it allows the brass of the neck area to slip backward and fill the shoulder, instead of drawing brass from below.

Mine might be an extreme case, because of the tight neck in the custom chamber, perhaps "standard" necked Ackley chambers don't need oiling in fireforming.

So while fredj338 warns about oiling the cartrige, I warn about checking each and every fireformed case for incipient case head separation, no matter what method is used for fireforming.

-HF

[runfiverun]

when i fireform for my ackley i just use a normal load and go shoot it.
the cases form better, and it don't take two or three tries.

[warf73]

When I was fire forming my 22 cheeta brass I added XX grains of red dot powder (can use what ever you like) then filled the case to the top with COW. I then plugged the case with bees wax (shoved the case into the wax cube up to the shoulder) then fired.
Just a note when fireing case loaded this way, the wax will put dents in a steel door at 10 feet........ yup the things that happen when winter gets a hold of ya :)

[Southern Son]

To fireform my 22/250Imp I just loaded up the cheapest 55 grain projectiles I could locate, seated them long, right into the rifling and put a little crimp on it. Only used a mid range load from a manual for the powder (I think it was 2206H, what you guys buy as H4895).

[stubshaft]

For my 257AI I just used 7X57 brass necked down. I have fireformed them with 257 Roberts brass but have found that not all chambers are cut to the proper dimensions. Since thaat time I have necked the cases up and then formed them with a false shoulder that was seated in the chamber. Then fully fireformed them with about 8 - 10 grains of Red Dot or Unique and a toilet paper ball in the case mouth.

[curator]

When fireforming cases I use a medium load and seat the bullet way out so that it contacts the rifling leade and pushes the head of the case hard against the breech/bolt face when chambered. When the cartridge is fired, all the expansion is neck and shoulder. This results in cases with no expansion/stretching of the brass near the case head. Works particularly well with AI cases and with mil-surps with generous chambers/headspace like the Lee Enfield .303 British.

[405]

When fireforming cases I use a medium load and seat the bullet way out so that it contacts the rifling leade and pushes the head of the case hard against the breech/bolt face when chambered. When the cartridge is fired, all the expansion is neck and shoulder. This results in cases with no expansion/stretching of the brass near the case head. Works particularly well with AI cases and with mil-surps with generous chambers/headspace like the Lee Enfield .303 British.

That is the best way to do it!

I think I've tried every way- Unique w/ COW waxed plug, regular Jbullet load, regular cast load, BE with paper, BE without paper and shot straight up, etc.

But, jamming a cast bullet into the lands then using at least a medium load will do the best job.

[RevGeo]

I too load a medium load in a standard case and fire my AIs. I have a 30-40 Krag AI and a .22 Sav HiPower AI. Both are rimmed cases that headspace on the rim, and results may be different with a rimless case.
I have never lubed a case before fire forming.

George

[405]

Yes, with straight walled rimmed cases just load and shoot. But, in those instances where it's a rimmed case with a shoulder AND the gun has a little excess headspace then it's worth a try to set the headspacing on the shoulder during fireforming by the bullet into the lands method. But, with levers and pumps that may not have very much camming power it could hamper slick chambering after 2-3 loadings. Then it's back to full length sizing, letting the case headspace on the rim and if there is some headspace slop in the gun- just have to live with limited case life.