Thread: Fire forming 270 to 280ai

Evening fellas

Fire forming is a new exercise to me so I'm after abit of advice before I rip into it.

Rifle is a new kimber with control feed action

I've picked up 100 new winchester 270 brass to turn into 280ai.
I have 5 pound of old rl22 and some cheap 7mm 140gr Speers to do the fire forming with.

Do I just lube the inside neck of the 270 case, run it through the 280ai die, fill the case with a medium load of rl22 and projectile then go shoot it?

Will I have head space issues and do I need to seat the projectiles to jam the lands to counter this?

Have I missed anything?

Evening Trav.

Generally I prefer to use the false shoulder method over jamming bullets into the lands, but in saying that, there is nothing wrong with jamming. I also use the longest bullets in the caliber I can get for FF.

I'd anneal the 270 cases, run them through the 280 sizer, charge the cases with a save load, seat the bullets so they'll jam into the lands and test.

Your not missing anything,

Ahhhhhhhh, yeah maybe. I'd be a bit more cautious than what your method lays out but your general process is right.

I'd be getting the water capacity of the .270 and the .280AI and working out the percentage difference in terms of capacity. Then confirming the start load of RL22 in the .270 isn't under the safe start load for the .280 and double checking it!

What you have with fireforming like that is a known excessive headspace condition and you are intentionally shooting it... How you work around it is by 'correcting' the headspace to secure the case head against the bolt face - either by creating a false shoulder by necking up and back down or jamming the pill into the lands and shooting it that way. Jamming the pill into the lands is the option that gives the steepest pressure curve hence a bit of caution in making sure the load is what you think it is... Against that, blowing the case shoulder out does absorb some energy though its theoretical mostly.

The .280 and AI cases have longer headspace than the .270 so the correct way is to neck the cases up to .30-06 and then set the shoulder back to a hard close in the .280 AI die. You have missed that the longer headspace needs an extra step. The headspace of the .280 is longer than other 06 based cases to stop them chambering in a .270.
GPM.

I do have a set of 30 06 dies some where, should I run the 270 brass through the 06 dies first and then through the ai die?
Will anneling help new brass

Originally Posted by Trav-6mmrem

I do have a set of 30 06 dies some where, should I run the 270 brass through the 06 dies first and then through the ai die?
Will anneling help new brass

You just have to run the sizing button in and out of the neck and preferably not FL size them. When you run the cases into the AI die make sure you have decent resistance on closing close so don't FL size with the die hard down on the shell holder. A bit off trial and error will be needed to achieve this. You will only have a tiny shoulder to achieve this. Necking down is preferable to necking up as it stops part of the shoulder being formed into part of the neck. .270 and .280 cases are the same length and cases usually become shorter when necked up and longer when necked down. I would anneal after fire forming.
GPM.

It’s easier starting with 2506 brass, as the shoulder & neck length are closer to 280ai. You can use 270 cases but there’s a lot of trimming to do on the neck to reduce back for correct COL. When I’ve done it I’ve run them thru a 280 neck size die, trimmed to SAAMI COL then fire formed. Hornady do a universal 7mm neck die.

An alternative method is to use a shotgun powder to fire form the cases, so you won't be wasting bullets. When I fireform 303 cases into 7x57R, I anneal the neck and shoulder, then open the neck of the case to 30 cal and then neck it down gradually in the 7x57 full length die until I find a firm fit of the case into the chamber with the action closed. This gives me a group of cases which have a tight headspace in the rifle chamber. Then load the shotgun powder (I used Green Dot) into the cases as a series of cases with load increments. A square of toilet paper in the neck holds the powder in the case. I fired the cases from the lowest charge up until I found the correct level of charge that formed the case enough. 18gr gave a fully formed case body with slightly rounded shoulder corners. 19gr did not make the shoulder sharper. That comes with shooting the cases with a bullet.

Originally Posted by rupert

An alternative method is to use a shotgun powder to fire form the cases, so you won't be wasting bullets. When I fireform 303 cases into 7x57R, I anneal the neck and shoulder, then open the neck of the case to 30 cal and then neck it down gradually in the 7x57 full length die until I find a firm fit of the case into the chamber with the action closed. This gives me a group of cases which have a tight headspace in the rifle chamber. Then load the shotgun powder (I used Green Dot) into the cases as a series of cases with load increments. A square of toilet paper in the neck holds the powder in the case. I fired the cases from the lowest charge up until I found the correct level of charge that formed the case enough. 18gr gave a fully formed case body with slightly rounded shoulder corners. 19gr did not make the shoulder sharper. That comes with shooting the cases with a bullet.

That method was recommended to me by Robbie Tiffen for blowing out 223 cases to 6mm.
But no gradual sizing. Just fill them up with fast powder and bang, it's done.
Obviously trimming to length was required.

280ai is a great cartridge. Before the nosler SAAMI I used most of the different methods of fire forming and with some care they all worked. There are some different versions of the chamber floating around and some poor rechambering jobs resulting in longing than spec headspace. The worst was a rechamber that would give head case seperation on the initial firing of factory 280rem ammunition. Today we dont need to fire form, just buy the correct brass with the corect headstamp.

https://www.gunworks.co.nz/shop/category/280-ackley

Greetings all,
A few notes on the AI cases follow. Parker Ackley developed and wrote about his AI cases back in a more innocent time when pressure testing was limited. The two most popular were probably the .257 Roberts AI and .30-06 AI. Later the .280 Rem AI was added. All of these cases are loaded to low pressure by the factories, the .257 Roberts especially so. Case forming was easy as the chambers were set for a slight crush fit at the base of the neck to allow factory rounds to be fire formed. The barrel had to be set back a thread to allow this be done. Huge increases in velocity were claimed achieved partly by increasing pressure to .270 levels and partly by going well beyond. As I said it was an innocent age, sometimes called the intrepid years of handloading. More recently the .280 AI has been made a factory cartridge which has provided some pressure tested handloading data. Out of interest I calculated the probable velocities for the .280 Rem at .280 AI pressures and found the gain to be minimal, in the 30 to 50 fps range. Other pressure tested comparisons for the .30-06 AI with its parent case showed the same thing. This does not mean that the AI cartridges do not perform well, they do, but the Ackley shoulder does not by itself provide vast increases in velocity as often claimed when all else is equal.
The .280 Remington has the shoulder set forward about 1.5mm from the other 06 based cartridges so the round can't be chambered in the .270. As both .280 Rem and .280AI cases may be hard to find this complicates forming appropriate cases. Both the .270 and the .280 cases are over 1mm longer than the .30-06 and other 06 based cases due to being based on the .30-03 cartridge, an earlier form of the .30-06. The .270 case will give the right case length but part of the neck will be formed from the case shoulder which may create a donut problem and the .30-06 case will wind up short. In either case there will be a grossly excessive headspace to deal with which will need a false shoulder, a jammed projectile or both. The C. O. W Cream of Wheat method with a fast powder and topped of with Cream of Wheat is an option as well. That 40 degree shoulder does look neat though. I had a .30-06 AI for a bit but never did much with it and it has long departed.
Regards Grandpamac.

Originally Posted by Trav-6mmrem

Evening fellas

Fire forming is a new exercise to me so I'm after abit of advice before I rip into it.

Rifle is a new kimber with control feed action

I've picked up 100 new winchester 270 brass to turn into 280ai.
I have 5 pound of old rl22 and some cheap 7mm 140gr Speers to do the fire forming with.

Do I just lube the inside neck of the 270 case, run it through the 280ai die, fill the case with a medium load of rl22 and projectile then go shoot it?

Will I have head space issues and do I need to seat the projectiles to jam the lands to counter this?

Have I missed anything?

Save primers, powder, bullets and barrel life by getting a hydraulic form die: https://www.whiddengunworks.com/hydraulic-form-die/

or (scroll down) https://www.hornady.com/reloading/dies/custom-dies#!/

Cheers for the info guy, this is exactly what I was after. I'll give the false shoulder a go and play with sizing back down in the ai die to a tight fit.

In a perfect world I'd buy norma 280ai brass. However, the way the economy is going, new winchester 270 was less than a 3rd of the price. I also like the idea of furthering my reloading capabilities

Id guess when its all added up it will be a more expensive option but having spent half a life time playing with ideas and finding out the slow and expensive way I get where your coming from. You cant put a price on learned knowledge. Necking up has the potential to cause donuts so keep an eye on it, you may need to neck turn or use an internal reamer.
This is some lapua 3006 brass I formed with the false shoulder( the case on the right is a factory nosler 280ai) when I was messing around with different brass and wasting time and money