Home Forums Reloading Big Game Rifles 280AI fireforming

I’m reloading New 7mm Express REM. brass, (280 REM.) I got 5 packets of brass from about the 80’s, I’m just putting them thru a .280 fl die, 160 gn Speer Hot Cor , and loading a mild (RL 19. 50.5 grains) load to fire form in my rebarrelled Win Mod 70. in 280AI (sammi spec.. ) , (sub MOA rifle), I have the projectile touching the lands, I am getting up to 30% loads not firing, I have to rework (re cock) to fire the second attempt, some 3 times?? primer appears to be well struck by the firing pin, these misfires only happen when fire forming, all other’s fire and fire form perfectly? Has anyone got any insight to why not firing?
They also show a sign of pressure as primers are “fairly flattened”.?

* the fire formed brass has then been reloaded to 280AI and shoots well, so the fire form process works well.
Thanks for any input, ideas.

Jay

Not hard enough into the lands, has to be enough to keep the case pushed against the bolt face.

Yup. Seat it to the lands more and give it a harder crimp.

RL 19 seems like an extremely slow burning powder for fireforming. You want the case to hit the pressure spike quickly and stick to the chamber. If the bullet jumps away from the bolt and is fireformed it will stretch the case which is not good.

Never did a 280AI but fireformed a thousands of 7mmTCU and 30-30 AI and always used a moderate load of a faster powder that is used for the standard loads with a cast bullet. You can even use pistol powders and save a bullet. Look up the Cream of wheat (COW) method.

or neck it up and false shoulder it, which makes a lot of sense

Don't run them through the FL die.

Seat the bullets firmly into the lands.

Don't use mild charges to do this. The fireform load should be fairly crisp.

I do it like this!!

I fireformed about a hundred R-P 280rem brass with older Hornady 154gr Interlocks and the midweight book data for 280rem of Dupont era IMR 4895. I seated the bullets out to where they were jamming in the lands and had zero issues with a fail to fire. Brass came out with good sharp shoulders and I had no necks splitting or any other issues.

Other fellas here posted it, but go with a heavier powder charge and definitely seat your bullets longer. You should feel a relatively tight fit when you close the bolt. If your whole loaded round moves forward when you pull the trigger, then there isn't any resistance to detonate the primer.

Some articles recommend the cream of wheat method, but if you do that method, your still going to be using primers and your shoulders on the newly formed case wont be as sharp as an actual fire forming load. Why not get some trigger time in during the process. You might also be surprised at how accurate the fire forming loads might be also.

You should have fhuqking listened,the FIRST fhuqking time. Hint.





Headspace very MUCH matters and you are fhuqking it up,in AMAZING fashion. Hint.


Just sayin'................

isnt the 280 ackley suppose to headspace on the shoulder neck junction ....thats why you can fire 280 remington in the chamber

Yes, and it does. Have used .280 factory loads which fireform as intended and also Stick outined the easy way which I also use, which is .30/06 brass sized in a .280 die to get the neck and shoulder point for headspace. Thereafter, the fired cases are loaded using the AI dies, as I have both sets. Either work fine for the initial foreforming load.

so being pushed harder into the lands will not solve the problem correct ?

The OP isn't having trouble with case forming he's having misfires.

The way to prevent that is to keep the case from being shoved forward by the firing pin.

KEY is to control Virgin headspace. Tolerance stacking is a real thing and Theory doesn't always align with Application. One thing is for fhuqking SURE and that is Virgin Lapooey '06,won't chamber in ANY 280/280AI. Hint.

With initial and subsequent FINITE headspace control,Safety is bolstered,reliability assured,case life muchly improves and Accuracy/Precision will be bolstered to boot,along with ES/SD being minimized. Hint.

False shouldered Lapooey far left,formed 280 SALAMI amidship and Six Twat-Six for Giggles. Hint.



Just sayin'..............

Thanks for all the feedback and advice from the forum, the consensus seems that if I persevere with my method of fire forming, is to seat the projectile further into the rifling, and use a “stouter” load of faster powder, I have some AR2206H same as H4895, and there is a recommended load for use with a 160gn
Projectile in the Lee book, so I will load up 4 to see how they go, a mid range powder load.
I will also attempt to size down some .30/06 brass (Norma) that I have, as the other option to use, as also suggested from the responses.
I will try to get this done and tested over next few day and report back if the misfires disappear.
Jay

Shouldn’t have a headspace problem when firing 280 in a properly cut 280AI chamber. Maybe need to talk to the smith who rebarreled it.

If,might and maybe is for DUMB Fhuqkers. Positive headspace is a rifle's BEST friend and easily arranged,for the astute. Hint.

POS Pre-64 70 264 Win here,wearing 7mm RemMag Virgin Positive Headspaced False Shoulder. "Form" load sized brass far left,loaded round amidship that will Smooch lands to boot and fireformed case far right. headspace determined and controlled,long before the first primer was seated. Hint.







Sizing Dies reliably fhuqk alotta folks up. Don't move ANY brass,less very good reason. Hint.

Just sayin'............

Very nice!!

Thanks for all replies and suggestions/things to try, the consensus seems to be that with the process I am using is to seat the projectile out a bit further into the rifling. I have some AR2206H (H4895), faster powder, and I will try a mid range load, as per the data in the Lee book. And as all the fire formed brass that I have done in this manner are working ok when loaded to 280AI, and with in spec. I will do the seating out further first, and I will do the resize of .30/06 brass also, as I have some new brass on hand.
* I have used in the field and taken Deer with some of my fire formed brass already, so I am confident that it sizes to the chamber dimension and the brass so far, accurate, no splits etc…
Jay

This won't help with your problem but it is always good to anneal your case before fireforming. OT but something to think about.

I like to neck up to 30 cal and false shoulder as well (new brass only). Works for me.