280AI won't chamber

[codyadams]

Here is my guess...
Too much neck tension. Or, seating stem hitting the case mouth due to die not being set up quite right. Causing the bullet or stem to actually push down the shoulder, causing a very slight bulge in the body just below the shoulder. Meaning it won't chamber.

Pull the bullet, run it back through a FL die to resize body, trim case neck, back seating die out 1/4 turn, reload, shoot to fire form again.

This. Only thing I would add is measure how much neck tension you have after FL sizing the case, make sure you don't have too much. Measure the case length to confirm that it needs trimmed, and properly chamfer. If you have an abrupt edge in the sleeve that centers the bullet on the seater die, sometimes it can catch the case mouth. On one of my dies that was bad about doing that, I chamfered it slightly with a dremmel so it wouldn't catch the case mouth so badly.

 

[longbowelk]

Results after bullet removal, I retrimmed the case, only a tiny amount removed, the outer edge of the brass felt like there was a lip so I debuted it until it was gone. The brass chambered ok so I reloaded it. Problem seems to have been the lip. Looks like my normal deburring wasn't enough. Thanks for all responses.

 

[longbowelk]

Results after bullet removal, I retrimmed the case, only a tiny amount removed, the outer edge of the brass felt like there was a lip so I debuted it until it was gone. The brass chambered ok so I reloaded it. Problem seems to have been the lip. Looks like my normal deburring wasn't enough. Thanks for all responses.

Deburred not debuted...

 

[VLD Pilot]

Deburred not debuted...

How was the over all length of the case ? Looked too long in the picture. May want to check the Saami spec for trimmed length also.

 

[Legionnaire]

To my eye, it looks like the shoulder is pushed to more than 40 degrees. I've done that by having my seater die turned in too far; it shouldn't contact the case mouth. That wouldn't explain failure to chamber, though ...

 

[VLD Pilot]

To my eye, it looks like the shoulder is pushed to more than 40 degrees. I've done that by having my seater die turned in too far; it shouldn't contact the case mouth. That wouldn't explain failure to chamber, though ...

Your right it does. Funny thing is, the one on the left is the one that looks like it was crunched yet the neck looks longer and case looks taller. Seems as tho the other case would be longer.

 

[Legionnaire]

Well, if the OAL/neck was too long on the cartridge on the left, that could explain how the case mouth hit the seater.

 

[VLD Pilot]

Well, if the OAL/neck was too long on the cartridge on the left, that could explain how the case mouth hit the seater.

And why it won't chamber !

 

[Alibiiv]

I am working on getting my 280AI off the ground you might say. I've been fireforming Hornady 280 brass and doing a 2nd firing with midrange AI loads. Prior to my last session I was prepping the 1st fired rounds that yielded me the headspace of 2.116 to 2.118. I resized and primed them and prior to powder and bullet I checked each one to make sure they would chamber. All passed that test. Next I put the powder and 162 gr Hornady SPBT bullet in just off the lands about .020. Now comes the problem. All the rounds were successfully shot and yielded a final headspacing of 2.117 to 2.1175 except one. See picture below showing the loaded round that would not chamber next to a successfully 2nd fired casing. When measured with the Hornady headspace tool it still shows to be 2.116 where it started. I am not sure but it looks like a false shoulder may be showing. Also, the shoulder looks messed up . Is it possible that when I rammed the bullet in the brass, the die possibly caused the false shoulder or the sort of flattening of the shoulder? I am using the Redding 280AI dies along with the .014 Redding competition shell holder.

Curious to know what reamer your gunsmith has and what used to chamber the rifle. There's the Nosler ".280 Ackley Improved" (SAAMI) version, then there's the original Ackley Improved version of the cartridge. It will be important to find out which .280 Ackley Improved that the rifle is chambered in; SAAMI or original. The original .280 Ackley Improved used the parent case of .280 Remington @ a case length of 2.540 thousandths. The Nosler (SAAMI) .280 Ackley Improved cartridge that is being produced has a case length of 2.525 thousandths of an inch; a .015 thousandths of an inch difference in length. If you are using the original .280 Ackley Improved dies in the SAAMI chamber the brass is .015 thousandths longer and jamming the shoulder back. Or you could have the incorrect dies for the chamber in your rifle; what are you using for dies?. The dies have to match the chamber of the rifle or.....you will go crazy trying to figure out what is going on with the fire firefoming for this rifle. I suspect that this is confusing, thank Nolser for this mess!! A year or so back I was going to build a .280 Ackley Improved until I ran into this confusion, built a .270 Ackely instead.

 

[DHBWA]

Either set of dies set up correctly will work for either chamber. Additionally. The dies are not going to lengthen the brass on there own....

 

[VLD Pilot]

Either set of dies set up correctly will work for either chamber. Additionally. The dies are not going to lengthen the brass on there own....

The chamber decides what the brass will end up looking like after it's fired. Once dies are set up for that cartridge (neck, shoulder) it's loaded and it either chambers or it doesn't. It should chamber fine technically. If it shot and extracted with no issues, that same brass should work.

 

[montana west]

I have owned two 280 ackley Imp and no problems with them. However at one time there was a 7mm /06 and I owned one of them on a 2.494 case in stead of the 2.540 case of the 280. the difference is 1 mm and that make a lot of difference .. the 270 winchester is 2.540 but the sholder is the same a s the 06 case and because of this you cannot fireform 270 win cases in to 280 remington cases without the neck being enlarged to at least 308 or larger so you will have a ring on the neck for head spacing. thus you may need to adjust something, but you must have a ring to headspace for fire forming.. Now I have had problems like this and the neck needed trimming and this solved the problem . all rifles ae differednt but you will solve the problem and you will like the 280 AI .

 

[CTK]

To my eye, it looks like the shoulder is pushed to more than 40 degrees. I've done that by having my seater die turned in too far; it shouldn't contact the case mouth. That wouldn't explain failure to chamber, though ...

when this happens a rounded ring forms at the shoulder case junction. And that's just one of the problems here.

 

[Blackhawk]

This. Only thing I would add is measure how much neck tension you have after FL sizing the case, make sure you don't have too much. Measure the case length to confirm that it needs trimmed, and properly chamfer. If you have an abrupt edge in the sleeve that centers the bullet on the seater die, sometimes it can catch the case mouth. On one of my dies that was bad about doing that, I chamfered it slightly with a dremmel so it wouldn't catch the case mouth so badly.

I have encountered and sub sequentially over come these issiues and, without going into associated neck tensioning and the use of appropriate bushings all of which have been thoughtfully addressed on this web post.
To that End I will offer up my thoughts.

Observations
This case from your photograph indicates where the neck and shoulder meet is obviously deformed and therefore rendered unusable !
To chamber such a round is flirting with disaster, and I am glad that were even able to safely perform an extracaction.!
Your loaded rounds condition which is indicative of incorrect neck hardness may also the result of over or under lubing your case during either the fl resize , or most likely exerting too much pressure on your press during the bullet seating operation ( again to due a case neck that was too hard )
My guess is that judging from your photograph in which your case shows no discoloring , normally a bluish- brown color which may extend above or below the area where the case neck and shoulder meet your cases have been annealed without reaching the correct temperature which would result in an inconsistent neck hardening during your annealing process! ( i believe that your estimation the of time in the flame as well as the flames intensity are themselves your villain's)
It would appear that your culprit is your annealing process and the time your brass cases are being annealed !
I suspect that you reevaluate your entire annealing process as your accompanying photograph indicates.
Please Read On .
Questions :

1) Are you using templiaq 700 high temperature paste?
2) Are you annealing by hand , or by using a machine?
3) Are you using brass from the same lot# , and the same manufacturer ?
Answers:

1): Templiaq 700 degree paste will tell you how much dwell time is actually needed in order to achieve and maintain proper annealing temperature. Yes it is expensive but if you are using a machine for annealing you only need to set up your dwell once. ( brass cases different sizes and calibers will need to be adjusted accordingly )

2): If you are annealing by hand you will achieve inconsistent temperatures which will result in your cases necks exhibiting signs much like your FL resized brass sample .
Tempilaq will get you a constant temperature simply by its discoloring and subsequent melting at the correct temperature.
This will require you to either brush each rifle case neck , or keep a close count on several dipped cases in order to establish a mean time while annealing.
Example lets say you have coated two cases .
Case#1 discolors at 4.5 seconds ,as counted in your head. Case#2 discolors at 5.0 seconds. A mean time would be 4.8 seconds. For your purposes 5 seconds will suffice. .If you can have someone with a stop watch time you all the better, but your results will still be the same unless you can manually set a start and stop time and even then your results are questionable.
Possible Solutions:

Please watch your flames temperature by controlling your flame to brass neck distance, as well as an even rotation of your brass shell cases and time subjected to your cases necks themselves under heat , making certain to keep the flames translucent color just beyond the tip in constant contact with your case neck at the point where the neck and shoulder angle begin.
Consistency is the key word here. and to that end Teplipaq 700 paste is a step in the right direction.
Better yet is to invest in an annealing machine if you don't own one.
If you do please make the adjustments as noted above.

OBTW I'm using the Annealeeze 2 made by Jeff Buck.
This unit will handle every thing you throw at it without any hiccups. The price point is nice as well (check them out on U-Tube)
Hope This Is Helpful !