Ackley Improved
- Thread starter Savage88
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rscott5028
Well-Known Member
PO Ackley did a bunch of testing in the 50's-60s with wildcats by reaming chambers such that the shoulder was moved forward and the angle changed to allow more powder and hence more velocity.
In most cases, you simply fire-form the brass in your AI chamber using the parent cartridge. In some cases, you can purchase brass with the xxx AI headstamp.
This was very successful and popular with some cartridges to the extent that we now have factory rifles and ammo for ones like the 280AI.
In other cartridges, the difference was minimal.
Lots of info if you google it...
P.O. Ackley - Wikipedia, the free encyclopedia
-- richard
In most cases, you simply fire-form the brass in your AI chamber using the parent cartridge. In some cases, you can purchase brass with the xxx AI headstamp.
This was very successful and popular with some cartridges to the extent that we now have factory rifles and ammo for ones like the 280AI.
In other cartridges, the difference was minimal.
Lots of info if you google it...
P.O. Ackley - Wikipedia, the free encyclopedia
-- richard
Thanks for the info!
But what i guess im wondering is I have a .243 and if i get .243 AI rounds, can they be shot from my normal .243??
Joe King
Well-Known Member
no you wont even get the bolt closed
Savage88,
Even if you can, why would you want to do that ... defeats the purpose of fireforming it into an AI ??? lightbulblightbulblightbulblightbulb
Even if you can, why would you want to do that ... defeats the purpose of fireforming it into an AI ??? lightbulblightbulblightbulblightbulb
Joe King
Well-Known Member
lol yea that too
Even if you can, why would you want to do that ... defeats the purpose of fireforming it into an AI ??? lightbulblightbulblightbulblightbulb
ADDED:
Don't let Ackley's research 50+ years ago stop you from venturing out of the norm. There's been lots of technological advancement since then; powder, primers, bullets, barrels, etc ...
I personally am finalizing a .270 AI because the naysayers said it is not worth it ... that should stir up the pot.
Joe King
Well-Known Member
Why wouldn't it be? 30-06 AI and 280AI are great chamberings, I would think a 270 AI would be no less.Even if you can, why would you want to do that ... defeats the purpose of fireforming it into an AI ??? lightbulblightbulblightbulblightbulb
ADDED:
Don't let Ackley's research 50+ years ago stop you from venturing out of the norm. There's been lots of technological advancement since then; powder, primers, bullets, barrels, etc ...
I personally am finalizing a .270 AI because the naysayers said it is not worth it ... that should stir up the pot.
Joe,
Exactly! gun)
Ed
Exactly! gun)
Ed
It just doesnt make sense to me. From what ive researched, the gains are not that outstanding. It would make sense, if it was a small improvement to the cartridge to gain that little bit extra emfff without gettin a whole new rig. But having to buy a completely new rifle to get minimal increased performance doesnt seem worth it to me. Buying a larger or more powerful caliber makes more sense to me.
Please correct me if im wrong. Im curious!!!
Joe King
Well-Known Member
Look at it this way. A 280 AI is only a small step behind the 7mag with about 10 -15% less powder, so efficiency goes up, if you have a rifle chambered to AI chances are your going to have the action tuned as well so in the end you'll end up with a highly accurate rifle that none of your friends have (exclusiveness)
Lefty7mmstw
Well-Known Member
Or you can ream out the chamber in your 7 rem and get some real speed without pushing the pressure envelope. The 7stw is just that, and it will do 3400-3450 fps with 140 grain bullets without trying. I like to go with a bigger round rather than pushing it.
I like the 270 and 280, but I leave them as they are and go a lot bigger when I want more.
I like the 270 and 280, but I leave them as they are and go a lot bigger when I want more.
J E Custom
Well-Known Member
The idea of the AI (Improved cartrige)is to up the performance in any cartrige with out having
to make major changes in the rifle. And if set up right, be able to fire both the parent ammo
and the Improved ammo in the same rifle.
Example: If you build/buy a rifle in 280 remington and have it rechambered in 280 AI and use
the same head space gauge, You can fire eather round in it using the rifle as is because the
rails,follower,bolt face and extractor remain the same.
The ballistics of the 280 AI are 100 to 200 ft/sec faster using the same bullet in the 280 Rem.
With the lighter bullets the 280 AI will approach the 7mm Rem Mag velocities. (But not with the
heaviest 7 mm bullets).
If you went from a 280 Rem to a 7mm Rem Mag the bolt face would have to be enlarged, a new
extractor would have to be installed, the mag follower should be changed and the action rails
would have to be opened up, plus a total rechambering. Also you would go from a shouldered
head spaced case to a belted case. (Sizing requirements are somewhat different between the two
case types.
The other thing about doing an Improved chamber is improved brass life.
J E CUSTOM
bronco
Well-Known Member
I absolutely love my 243AI and 280AI. It's a more efficient design. It's provides more FPS on the base cartridge, much better case life and a cool factor. The gains are very apparent even when done on a "shorter/sporter" length barrel. It's great way to "Freshen up" an older chamber. It's not for everyone, but it's great for me. It's makes the most of the platform you have without having to step up into the next higher case size. I have never had any feeding problems or any other complaints to speak of.
Here is a scenario: 2 hand loads off a 280 case with 140AB and a 200yrd zero 280REM @ 3000 and 280AI @ 3200
To a shooter taking shots out to 300 the difference is negligible, about an inch. Now stretch that to 600 yards and the 280AI shoots 9" flatter and carries 200ft lbs more energy. For the 1000ft lbs recommendation for taking deer sized game, the 280REM will get to 680, while the 280AI will get to 780 before dropping below 1k ft lbs of energy. It just depends on the shooter and his environment if it's worth it to him.
Savage88, You don't see the value in it because you are still shooting factory ammo. When you start reloading you will open yourself up to a lot of great options that won't require you to go to a higher case size to get more power. With the scenario above, you get almost 7MAG performance with less powder and recoil.
Here is a scenario: 2 hand loads off a 280 case with 140AB and a 200yrd zero 280REM @ 3000 and 280AI @ 3200
To a shooter taking shots out to 300 the difference is negligible, about an inch. Now stretch that to 600 yards and the 280AI shoots 9" flatter and carries 200ft lbs more energy. For the 1000ft lbs recommendation for taking deer sized game, the 280REM will get to 680, while the 280AI will get to 780 before dropping below 1k ft lbs of energy. It just depends on the shooter and his environment if it's worth it to him.
Savage88, You don't see the value in it because you are still shooting factory ammo. When you start reloading you will open yourself up to a lot of great options that won't require you to go to a higher case size to get more power. With the scenario above, you get almost 7MAG performance with less powder and recoil.
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