280 Ack. Improved ? Question

[matty]

I built a 6.5x284 on a Remington L/A with a Mcmillian A-2 stock. For deer hunting and playing with steel at long range ( for fun ). I like it but my buddies 7mm Mag is a lot more impresive at the longer ranges, especialy if the wind is blowing. So I considered the 280 Ack Improved so I could use the action and bolt face I have now.
Just wondering how others have got along with this cartridge. Thanks

 

[bheadboy]

I have had two, both on 700 trued actions by Bobby Hart, 26" hart 9twist with high-tech stocks. they both shot in the .300's with Nosler140bt and Sierra 140 sbt they were in the .450- .500 with the 160's

the velocity I set on was 3150 as that is where the groups were the very best - I was easily able to get into the 3200-3250 range but did not feel I needed it for my hunting.

they are a very great choice brass easy to form and dies available form redding, a number of powders worked, I used h 4350 and h4832sc with equal results.

Bob

 

[CatShooter]

There are two versions of the 280 AI... make sure that you get the Nosler version. There is factory brass for it, and it the only SAAMI accepted AI cartridge.

And Redding states that when the inventory of dies for the older AI version are gone, they will not make dies for it any more.

 

[rcol317]

You won't be disappointed with a 280 AI. I've had several and the one I have now is my go to rifle. Mine shoots 168 VLD's @ 2,980 fps and that's a little faster than I can shoot them in my 7mm Rem Sendero. I don't know why maybe the action or barrel but I love the Ackley because less powder and less recoil. I also shoot several 6.5 X 284's the only advantage is the BC's of the 284 bullet. The point about the Norma is important when you look for a reamer. Good luck and good shooting

 

[DogBuster]

I am considering building a P-N tube...just haven't pulled the pin yet..
Have 100 new formed Nosler brass....along with a box of 180 SMK's just to fondle....looks like a wicked LR cartridge..mine would just be a LR steel banger on a Savage SA...either a new target action..or just pull another project down....my idea would be a minimum 28" no taper tube with P-N Vias brake...8T/5G.....280AI shooters ? 8T or 9T ? 180s would be my boolit choice.....

 

[mshelton]

It's a cool little cartridge, I had one for a bit but sold it after getting tired of dealing with crappy lots of Nosler brass. Do yourself a favor if you build one, buy 40 pieces of RWS 270 brass for a tad more than you would pay for the Nosler and fireform them with shotgun powder and cream of wheat. You'll have some of the best brass on the planet.

 

[flatlander]

Matty, If you haven't already committed to the 280 AI build, you might consider going with a straight 284 Win. If you annealed the necks of your Lapua 6.5x284 Norma brass, you could easily expand the necks to 7mm. Not that I have anything against the 280 AI - have one myself, and it's a good LR rifle. But even though the 280AI has approx. 6grs additional case capacity, I've not gotten any more velocity out of it with 180s than I do out of my 284s.

One other thing I should mention - if you're planning to run DBM, the 284 case, with its .500" body dia, feeds very smoothly out of AI 300WM magazines.

The 280AI requires the purchase of Accurate Mag's version of the same mag, or bending the feed lips of the AI 300WM mags to hold the smaller dia 280 case. Even then, it doesn't feed quite as smoothly as the 284. Accurate Mag makes a specific magazine for the 30-'06, and the 280AI case fits them perfectly. The only problem is that AM puts a delrin filler in the front .250" or so of these mags, which - combined with a shortened follower - make them too short for any of the heavier bullets in a 280AI. If we could get them to make a run of these '06 mags without the filler & with a longer follower, we'd have the perfect magazine for the 280 or the AI version.

 

[flatlander]

mshelton posted while I was typing my reply - why not go with RWS 280 brass? I've bought a couple hundred of these cases for my 280AI, and have no doubt that they're the best quality case available for the 280 or the AI version.

 

[mshelton]

mshelton posted while I was typing my reply - why not go with RWS 280 brass? I've bought a couple hundred of these cases for my 280AI, and have no doubt that they're the best quality case available for the 280 or the AI version.

You probably could go with the 280 if the length is right, I did a 25-06 AI and used 270 but if they are both the same length then it doesn't matter.

The reason for using the 270 (2.540 in) is that it is longer than 30-06 (2.494 in) brass, when you form the Ackley it draws up into the shoulders making the cases actually shorter so you end up with a larger gap between the top of the brass and the start of your freebore. I messed with this when forming brass for a 25-06 Ackley, pretty much the same thing as the 280 AI just 257 vs 284. If I necked down the 270 cases and trimmed them to where they would fit into my chamber (2.522 in) then fire formed them with COW they would draw up to an avg of 2.505, after trimming to a uniform length they ended up at 2.500 leaving a .022 gap. If I necked the 270 brass down to 25-06 then used a busing to further size a bit of the end to .257 I could chamber them without trimming and after fireforming and trimming they ended up being 2.515 and a .007 gap.

The second step I did is probably unnecessary but it gave me a bit of a better fitting piece of brass.

 

[bheadboy]

I never had a feeding problem with my 700s built by Hart, the case feeds like grits. used R/P 280 brass on all never a problem

Bob

 

[Rustystud]

In e last year I have built two 280 Remingtons and two 280AI. All shot very accurate but the 280AI shoots faster and will be right behind a 7mmMag in velocity and maybe a little more inherent accuracy. They do burn barrels out quicker. I suggest you try IMR7828 powder.
Nat Lambeth