Fireforming .280 AI from .280 Remington brass or .270 Win brass?
- Thread starter Alibiiv
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Just start out with 50 pieces of new Nosler brass. Use 30 cases to work up a good load, (rotate them and keep track of the number each has been fired) zero and practice and the other 20 for just hunting. Later on, buy another 50 pcs for a different bullet weight or style, do it again. 
Its only money, and life is short!
Its only money, and life is short! 
adk hunter
Well-Known Member
I have done the following...
1) Bought some .280 rounds and shot them for barrel break-in, fun and to see which off the shelf .280 was best in case of lost rounds.
2) Nosler brand new to work up accuracy loads. Saved time and gave me near perfect once fired brass.
3) Hornady really cheap in a 40% off sale on Cabela's and had the best time running them thru the resizing die with my son. Took awhile but boy did time fly while we were visiting. Might be the best value in the end!!
I have more brass than needed probably but I can just pull some new ones out if I want to throw together a batch of fresh ones.
1) Bought some .280 rounds and shot them for barrel break-in, fun and to see which off the shelf .280 was best in case of lost rounds.
2) Nosler brand new to work up accuracy loads. Saved time and gave me near perfect once fired brass.
3) Hornady really cheap in a 40% off sale on Cabela's and had the best time running them thru the resizing die with my son. Took awhile but boy did time fly while we were visiting. Might be the best value in the end!!
I have more brass than needed probably but I can just pull some new ones out if I want to throw together a batch of fresh ones.
Thank you for your suggestion and sharing your experience with making the rounds. And...any time spent with your son at the loading bench is worth every penny!!
MudRunner2005
Well-Known Member
Factory .280 AI ammo, or factory .280 Rem ammo? The reason I ask, is because you only mentioned Nosler and Hornady, and they're the only companies that make factory .280 AI brass and ammo...
Yes that is correct. My only fear is that the .280AI does not suffer the same fate as the .280/7mm Express did after a few years and the caliber fell out of good graces with the shooting community. Due to the caliber's popularity I do not feel that his will be the case, however.............. This is one of the main reasons that I am exploring the potential ways to get brass. I "really" have a problem when I see the price for the .280AI compared to .280 Remington brass, the cost of loaded .280 Remington ammunition is about 50% less than unprimed .280 AI brass.
From where I am sitting it really does not seem logical that making .280AI brass is more costly to make than .270 Winchester brass, especially at double or triple the cost!! I also feel that some of the ammunition manufacturers have taken advantage of all the anti-gun politics and have increased their prices considerable due to these adverse politics. What we used to get for reloading bullets is now the same price, however there are only 50 heads instead of 100 in a box. Pistol ammunition is oftentimes sold in boxes of 20 or 25 instead of the 50 rounds that we used to get!!!! And now I am seeing the same trend taking place with brass! And.....this ought to be another thread, will stay on track here. Thanks for getting back to me.
adk hunter
Well-Known Member
Actually both, but I was referring to shooting the regular .280's to do some barrel work and then had the brass formed to my chamber. I got a few nickel plated ones and they make a sexy combo for the short term with a 150 ABLR loaded up...
I understand no matter what I do these rounds and the fire forming will also be used to break in a new Lilja barrel on the build that I am having done. So whatever I decide the brass will be formed in a new chamber on a newly built rifle. I want this rifle to shoot better than I can shoot it, so the brass is a key piece of the system. I've got a bunch of .270 brass kicking around too. I could run the .270 brass through the .280 Remington dies and size the necks up, after that process I believe will have to trim the brass back for OAL on the case, however not looked that far into it as of yet. I live in New England so I have an entire winter to work the kinks out. It's going to be a lot like Christmas long after December this year!!
J E Custom
Well-Known Member
I recommend chambering the AI the way P O Ackley did and not having any issues with fire forming.
There are two distinct different AI chambers now days.
The Ackley way and the new SAMMI chamber. If you don't reload or don't want to fire form, I recommend using the new SAMMI head space gauge and reamer and buy the preformed brass.
If you want to shoot all other brands of loaded 280 ammo and /or brass, I recommend using the 280 rem head space gauge and chambering .004 thousandths short (No head space). this allows you to chamber factory 280 ammo/brass without any bullet seating tricks, and gives you great accuracy while you are fire forming.
Most people with rifles set up this way get hunting accuracy while shooting the un fire formed cases. It also allows you to shoot any brand of 280 ammo or cases except the Nosler. Some say you can fire the Nosler in an non SAMMI AI chamber(The dimensions of a true Ackley chamber), but I don't recommend it because of the fit in the chamber (Case head separation is a distinct possibility as MUD said).
Set up the way Ackley recommends, standard 280 loads can be use to fire form with no issues because the case is held in place with .004 compression and does not allow it to move. It also reduces the case growth to .004 to .006 thousandths in the fire forming stage.
Just my recommendation
J E CUSTOM
Rifleman513
Well-Known Member
I have not used the Horanady brass for 280 AI but have bought some for 257 wby when they started making it. I have no major complaints with any of the Hornady brass that I have used. For my new 280 AI I bought some Nosler 140 BT ammo at 31 a box and I'm shooting through them to break in and practice w/ the new gun. I will be surprised if my hand loads can match the accuracy and speed that I am getting with this factory ammo.
J E Custom
Well-Known Member
I saw this Video and It is flawed. When you chamber the 280 Ackley or the 280 SAMMI AI It is true that you can use the same reamer. "BUT" If you use the different head space gauges you will end up with different chamber lengths.
If you understand the relationship of the two and use the chamber dimensions of both (According to SAMMI) the body neck junction on the 280 Rem is 2.1924 from the case head. The 280 SAMMI AI body to neck junction is 2.1742 Making the chambers after fire forming .0182 different. with the .004 to .006 compression of the Ackley recommendation this will reduce the difference of the two chambers
to .0142.
Obviously, If you use the SAMMI head space gauge for both chambers, It will be a SAMMI 280 AI chamber but you may not be able to chamber a standard 280 Rem cartridge because it will be at least .014 thousandths long.
If you chamber it using the 280 REM head space gauge as Ackley recommended and try to shoot a Nosler 280 AI formed case you will end up with .014 to .018 space in front of the body neck junction and possibly have case head separation.
The Body taper per inch is just over .008 thousandths per inch on both cartridges so they will appear to head space the same but the shoulder will be located .014 to .018 different between the two.
So when you fire a Nosler SAMMI AI loaded round in the longer 280 Ackley chamber the case stretch will be .014 to .018 plus your head space (Normally .001 to .0015).
So a person has to make up his mind if he wants a SAMMI chamber or a Ackley chamber. As I have said before there is a difference in the chamber lengths and he has to decide if he wants to use every brand of 280 rem brass With the Ackley, or use only the Nosler brass
in the SAMMI chamber. If you do decide to use the Nosler SAMMI AI chamber in order to use the standard 280 brass you should full size it and bump the shoulder back .014 thousandths before loading and firing it the first time to prevent case stretch.
This is a safety issue and for sure a component issue.
I have chambered several dozen of both chambers and made it clear to the owners of the difference and the risk if this rule is not followed, and have had none of the problems discussed.
J E CUSTOM
