280 Remington Ackley Improved

[Red_Eagle]

I got my 280 AI barrel for my Encore today. 26" heavy contour factory barrel that the T/C custom shop sells through Midway. I have basicly 3 questions:

1) What would be the best powder? IMR 4350 or AA 3100?

2) Can you use 270 Winchester brass to form cases?

3) I've heard that the cases can be fire formed with out bullets using shot gun / pistol powder and sealing the case. Does anyone have source of information on this?

Thanks in advance

 

[thekyrifleman]

Use 280 Rem brass to fireform. Bullet against the lands and a low charge of powder and you are home free.

 

[F. Guffey]

270 bras is the same length but the shoulder is sit back .051 thousands, much easier to use 280 Remington, by design the neck on the 280 Ackley is longer than the 280 Remington case, when chambered the 280 Remington short neck jams up against the shoulder of the chamber at the neck and head spaces (sort of) this starts the forming process, the shoulder starts to form when chambered and finishes when fired.

30/06 cases to 280 or 270 is a bad ideal, the 30/06 is .040 shorter.

270 cases formed to 280, the shoulder on the 280 is forward of the 270 .051 thousands, if desperate, I would neck the 270 up to 30/06 then neck the cases back down to 280, this will give the case an appearance of having two shoulders, the old 270 shoulder and the new formed 280 shoulder, the 280 shoulder will allow the case to head space?

Loads, I form cases once, no corn flakes and reduced loads, when forming cases there is safety in the design, the case must fill the chamber and form the shoulder, the expanding cases reduces pressure.

Fast powder and shock, I do not recommend it.

Forming with disregard: The case when formed does not stretch as perceived, meaning if anyone measured before and after and keep records they would find necking a case up shortens the length, if they measured the case body length from the head of the case to the shoulder and from the shoulder to the mouth of he case they would be able to determine if the case compressed or the neck shortened, could be both, and when the fired the case fills the chamber, to allow the body of the case to expand the brass must come from some where, this brass from somewhere causes the neck to be pulled back causing the neck to shorten.

 

[Scorch]

You can make 280 AI from just about any case from 25-06 to 35 Whelen, but you will get best results using 280 cases and firing a light load to fireform. As R Guffey says, the shoulder on the 280 is farther forward than the shoulder on most 30-06-derived cartridges, which presents a problem when fireforming. Just start out with 280 Remington cases, you will be time and money ahead in the long run.

 

[Red_Eagle]

Range report

I took it to the range today. My 280 Remington rounds fire formed out just fine. I used a Hornady 100 grain HP over top of 48.6 grains of W-760 and a CCI 250 Magnum primer. I also fired one round made from a reformed 270 Winchester case. I made it before posting on here. You guys were dead right. It fire formed out okay, but thier was a noticable increase in recoil and some primer set back. It didn't pop, though.
The load I worked up for it seems to be a winner. I was racing the clock. I got there at 3 o'clock and it closed at 5. I used a 150 gr. Nosler Partition, 56.5 grains of IMR 4350, and a Federal 210 GM primer. Strang thing was it didnt even act like it wanted to group until I got to the 55.5 gr charge and the 56.5 grain load was all within 1". Usually I have the opposite problem. The start loads all group nicely and then the group explodes when I get to hunting velocity.
Is there any other 150 grain bullets that will hold togather in a 280 AI if the shot is taken at 150 yards or less, besides the Nosler Partition? My hand loading mentor recommed the Hornady SST & Interbond. Will Sierra Pro Hunters or Speer Hot-Cors stay togather at that velocity?

 

[azsixshooter]

Hey, don't forget to add your new caliber to your sig! I've wanted a .280 AI since I first heard about the second Nosler Custom in that chambering. Sounds like you have a real winner there.

 

[Red_Eagle]

I'm pretty pleased with it so far. if you decide to get one I recommend the Nosler Custum 280 AI brass. It's pretty expensive, about $65 for 50 cases. Worked great and no brass prep at all. It came chamfer / deburred, flash holes and primer pockets uniform. Well worth the money in my opinion.

 

[F. Guffey]

Red_Eagle, the 280 Remington case when fired in the Ackley Improved chamber goes through some changes (case body expands, shoulder forms and a longer neck is created) that effect pressure, once the case is formed the capacity increases, with the same powder, bullet and primer do not expect the components to have the same effect on accuracy after forming, the objective was to form the brass, now you are ready to develop loads.

What holds together? Nothing changed, a bullet that works for the 280 or 7MM Remington Mag works for the Ackley improved.

F. Guffey

 

[Red_Eagle]

Clarification

The load I developed was with: Nosler 280 AI brass, IMR-4350, Federal 210 GM primer, and a Nosler Partition.
I also took some R&P 280 Remington brass loaded with a start load of W-760 and Hornady 100 gr HPs.
As for the bullet question, what I really want to know is which conventional soft tip 284 diameter bullets areleast likely to fragment or separate if a shot is taken at 200 yrds or less at around 3,000 f/ps. I like Sierras in my 308, 270, and 30-06. But I've been told they will come apart on target at this velocity. What I want is a reliable bullet that is cheap enough to play around with. As impressed as I was with the Partitions yesterday, at $31.00 per 50 they are way too expensive to shoot on a regular basis.

 

[perley03]

Hornady InterLock 139gr

I was thinking of trying these. At $0.269/pc these should be right around your price range.

 

[ReloaderPlus]

Fire Forming Techniques for converting 280 Remington Brass to 280 Ackley Improved

I got my 280 Remington on a Ruger 77R action re-chambered to 280 Remington Ackley Improved several years ago. At the same time I had the action glass-bedded into a Ram-line stock that looks like it is find wood. I also had the trigger attended to and what was already a fine rifle became a much better one.
I have learned a few thing about fire forming the brass.
At first I tried to use a starting load of a medium powder such as IMR 4350 and 140gr bullets seated out to touch the lands. I found that the cases did not completely form and there was too much stretch in the case near the web.
I started to get head separation cracks when I was developing loads.
I tried a different technique that works extremely well. The steps are as follows:
1. Using 280 Remington brass I run and expander die for 30 cal into the necks
2. I run the cases through a neck sizing die for 280 but leave .050 of the expansion in place at the bottom of the neck.
3. I load near maximum loads of H450 (similar in characteristics as H 4831) with 140 gr bullets seated normally and not touching the lands.
4. There is resistance when I close the bolt to chamber the load, which tells me that the case is held firmly between the bolt face and the neck.
5. When fired in the 280 AI chamber the brass forms perfectly when measured with a case gauge. The shoulders are accurately formed and have very little case stretch near the web.
I have formed well over 200 pieces of brass with this method and every piece is within .002" to .003" on case measurement.
I chronographed these loads and instead of a muzzle velocity of 2950 fps they are running about 2500 fps. The bonus is that these loads make 3 shot groups averaging 1.25 inches at 100 yards.
One of the reasons I use this technique is that my chamber has a long throat or free-bore and therefore it is hard to seat bullets out far enough.
One of the things that is confusing to a person starting out to fire form brass for a wildcat is the nebulous term of a "light" load with the bullet touching the lands.
I have been very successful and safe with this technique.
Now that Nosler has chambered rifles for the 280 AI and produces brass and factory loads the procedure will be much easier.
I am glad I could see the outstanding potential of this cartridge.