Is Ackley an improvement? Tikka compatible?

[CBH Australia]

I have read doing an Ackley improved version of some cases is not always a real world gain.
I considered having it done on a .22-250 or a 7mm-08 simply because my smith has dies and was working on them.

Now, I am seriously considering having a .280ai built for me on a Tikka action.

The round has been standardised I believe and is available

How well do Tikka actions take this conversion? Specifically for the .280ai and any others is the sharp shoulder and feeding an issue?

Any feedback on the .280ai for a mid calibre hunting rifle?

 

[YancyW]

The 280 is likely the best beneficiary of the Ackley Improved system. I use it very often for hunting and it is a truly fantastic round. I have used it on elk and many plains game, with a 160gr A-Frame, it is extremely capable.

 

[Mekaniks]

The 280AI is very popular here in AK as a sheep round. Very good long range ballistics in a standard non-magnum action and non-magnum recoil for light weight rifles. Lots of availability to choose from bullet manufactures.
I don't have one, but a 280ai is on my short list of custom builds after I finish my next project

 

[CBH Australia]

The 280 is likely the best beneficiary of the Ackley Improved system. I use it very often for hunting and it is a truly fantastic round. I have used it on elk and many plains game, with a 160gr A-Frame, it is extremely capable.

I’m liking the idea of this. I’m reading published reloading data for it too see what performance I might get with the Australian made powders. There may be better performing options but looking at what I have and what I can source anticipating changes from time to time with imported options.

I’m thinking a 150gn projectile could be my go to. It would be nice if I could achieve 3000fps but I think it will come up short. I’m potentially considering a 22” barrel but I’m open to suggestion, particularly from actual recorded numbers opposed to theoretical velocity loss.

 

[Mekaniks]

I like the 140g bullet and based on the Nosler Manual I think could be loaded to 3000fps with standard powders even with a bit shorter barrel.

 

[GeoffB]

I have been running a .280AI for just over 25 years. Awesome caliber.
I have a 24" barrel on mine and my hand loads return 2940fps with a 150gr bullet.
3000fps+ would be a hot load in my rifle. I use the 140gr bullets at 3020fps on everything.
I have mostly used it on Aussie game - pigs, goats, wild dogs, fallow and red deer.
Hits them like the hammer of Thor.
If you wanted to chase Sambar deer then upgrade to the 160gr bullet.
If you decide to to take it back to Africa then I don't think you will notice the difference between the .280AI and the 7mm Rem mag you used last time.
Brass and reloading dies are easy to get over here in Australia.
I originally used standard .280 Rem brass and fire formed them back then as it was still a wildcat.
Rebel Guns in Brisbane have a set of RCBS .280AI dies and brass currently in stock.
The Tikka is an easy gun to convert to .280 AI.

This is my .280 AI built on a Win 70 and McMillan stock.

 

[Ray B]

The only issue that I have had with Ackley Improveds involves the box magazine. I had a 257AI built on an FN commercial 98 action. the magazine box tapered to the front, designed for the standard cases that narrowed as they went forward. The AIs were wider at the shoulder. As a result the shoulders were tight against each other and the sides of the magazine while the cartridge bases had space to move- due to the magazines width. the problem was if the base was down, the bolt wouldn't catch it to chamber the cartridge. To solve it the magazine box was widened at the cartridge shoulder so that both ends of the case were tight against the side of the magazine. Otherwise, there was no feeding issue- the 40 degree shoulder was not a problem.

 

[YancyW]

I’m liking the idea of this. I’m reading published reloading data for it too see what performance I might get with the Australian made powders. There may be better performing options but looking at what I have and what I can source anticipating changes from time to time with imported options.

I’m thinking a 150gn projectile could be my go to. It would be nice if I could achieve 3000fps but I think it will come up short. I’m potentially considering a 22” barrel but I’m open to suggestion, particularly from actual recorded numbers opposed to theoretical velocity loss.

You should be able to get close enough to 3000fps that you won't notice a bit of difference, even in a 22" tube.

I'm not sure what powders you have available to you, but H4831SC is very popular with this round here in the US. Ramshot Hunter powder is the one I have had great luck with, VV N560 is also mentioned often as performing well, that might be an option for you.

I personally think 150gr is the lightest bullet that makes sense, for me, the round really starts to shine in the 160 and up range.

 

[CBH Australia]

Thanks, for info.

I know a 20” barrel would be considered short for this round but would it be sufficient if I can do it on the cheap and get into this .280ai build?

I would later consider a stainless or carbon wrapped barrel but if I can get the other barrel in for a minimal outlay I would be keen, I’m yet to buy another secondhand rifle suited to the project but there are a couple available.

 

[CBH Australia]

It seems that the Australian ADI powders don’t seem to be the best options for .280ai. Their book velocities are way lower than what some other powders are said to produce better velocities. Hoping that equates to a flat shooting performance.
With the current carbon wrapped IBI barrels available to me I can only source 22” or 26”. 24/25 was about max preferred length for this project

 

[CBH Australia]

You should be able to get close enough to 3000fps that you won't notice a bit of difference, even in a 22" tube.

I'm not sure what powders you have available to you, but H4831SC is very popular with this round here in the US. Ramshot Hunter powder is the one I have had great luck with, VV N560 is also mentioned often as performing well, that might be an option for you.

I personally think 150gr is the lightest bullet that makes sense, for me, the round really starts to shine in the 160 and up range.

So your H4831 is Made here as AR2213sc. Repackaged in the US buy Hodgdon.
I’ve read on a forum that a 22” barrel won’t be long enough for a full burn off of this powder.
I simply don’t know, I’ve read plenty but and loaded lots but still not in the league of many here with experience or a chronic at this point.

Copied from my thread
It seems that the Australian ADI powders don’t seem to be the best options for .280ai. Their book velocities are way lower than what some other powders are said to produce better velocities. Hoping that equates to a flat shooting performance.
With the current carbon wrapped IBI barrels available to me I can only source 22” or 26”. 24/25 was about max preferred length for this project.

Any input welcome

 

[C.W. Richter]

The 280 is likely the best beneficiary of the Ackley Improved system. I use it very often for hunting and it is a truly fantastic round. I have used it on elk and many plains game, with a 160gr A-Frame, it is extremely capable.

In reality, the .257 AI and 7x57 AI are the greatest of P.O. Ackley's Improvements! 3,450 and 3,250 fps. The .280 is just the most commercially available. Another gun offered by corporate committee! lol It's ok, but .25-.26-.27 cases in 50gr+/- is where the greatest Improvements are found...

 

[YancyW]

So your H4831 is Made here as AR2213sc. Repackaged in the US buy Hodgdon.
I’ve read on a forum that a 22” barrel won’t be long enough for a full burn off of this powder.
I simply don’t know, I’ve read plenty but and loaded lots but still not in the league of many here with experience or a chronic at this point.

Copied from my thread
It seems that the Australian ADI powders don’t seem to be the best options for .280ai. Their book velocities are way lower than what some other powders are said to produce better velocities. Hoping that equates to a flat shooting performance.
With the current carbon wrapped IBI barrels available to me I can only source 22” or 26”. 24/25 was about max preferred length for this project.

Any input welcome

I honestly don't like getting past 22" for a hunting rifle, if I can avoid it. In some cases it just doesn't, a 300RUM or 28 Nosler with a short barrel is just silly. But I absolutely would build a 280ai with a 22", I would think twice about it.

I can get a 168gr Berger close 2900fps in a 24" barrel, so I still think you can get relatively close in your setup.

Do you have access to the Reloder line of powders?

 

[CBH Australia]

I honestly don't like getting past 22" for a hunting rifle, if I can avoid it. In some cases it just doesn't, a 300RUM or 28 Nosler with a short barrel is just silly. But I absolutely would build a 280ai with a 22", I would think twice about it.

I can get a 168gr Berger close 2900fps in a 24" barrel, so I still think you can get relatively close in your setup.

Do you have access to the Reloder line of powders?

I think Reloader powders have been available.
Powder has been hard at times and they blame freight and storage requirements for this.
At times it’s been hard to get powder let alone get picky.
Also being in a small town with one gunshop I’m not sure if he has a big variety. Even in my travels across my state at least it’s been the same story at times.

Moderately priced IBI barrels are only listed as 22” & 26” where I’m looking and the 7mm bore are the Carbon Wrapped.

7mm isn’t listed in straight stainless hunter have a carbon stock that would accept a carbon wrapped barrel.

 

[CBH Australia]

In reality, the .257 AI and 7x57 AI are the greatest of P.O. Ackley's Improvements! 3,450 and 3,250 fps. The .280 is just the most commercially available. Another gun offered by corporate committee! lol It's ok, but .25-.26-.27 cases in 50gr+/- is where the greatest Improvements are found...

By the image you show the 7x57ai is achieving what the .280ai does, then there is no point burning more powders or am I reading it wrong?

 

[CBH Australia]

@GeoffB
I think the difference between this and the rifle I used in Africa is obvious, the 7mmRM is used had a silencer. I don’t have approval to fit them on any of my firearms. .
I have read the .280ai is hot on the heels of the 7mmrem.

I look forward to hearing more about yours, all best it’s not so common a chambering for Australia it sounds like the ideal one.

 

[bruce moulds]

In reality, the .257 AI and 7x57 AI are the greatest of P.O. Ackley's Improvements! 3,450 and 3,250 fps. The .280 is just the most commercially available. Another gun offered by corporate committee! lol It's ok, but .25-.26-.27 cases in 50gr+/- is where the greatest Improvements are found...

anything on the 7x57 and 250/300 parent cases will have a big gain due to a significant gain in case capacity when the outdated taper is blown out of them on fireforming.
the 308 will gain far less percentage wise.
there are those who claim that the smaller capacity cases can beat the bigger capacity due to being more efficient or some other such tripe.
i recall one who told me that the 250/3000 ackley is faster than the 25/06 ackley because it is more efficient.
case shape is irrelevent to velocity, but capacity is relevent..
as long as you use the correct burning rate powder for the job.
the 7x57 ackley has close to the same capacity as the std 280 rem.
translated into english, at the same pressure and with the best powder, velocities will be the same.
if you want to have to fireform cases for std 280 velocities, go ahead and do the extra work, buy the more expensive dies, and burn out a barrel sooner.
the 280 ackley will be between the std 280 and the 7 rem mag, because it is between them in case capacity.
as a straight dingo gun it would shoot pretty flat with 120 gn vmax or the bit harder 120 gn sierra soft point.
140s of different construction offer a wide range of game opportunity with the same zero and shooting nearly as flat.
then up to 160s of various construction.
after that you have a 375.
such a rifle with a 24" shilen no 3 profile barrel or similar will do a lot of jobs very well.
fir a pure dingo only gun, a 25/06 or a 6mm ackley rem might suit more, but are very specialized.
the 280 or 280 ackley are just so versatile.
120 gn bullets have sectional density of 50 gn 30 cal.
140s the same s.d. as 165 gn 30 cal.
160s the same as 190s.
a nice compromise.
bruce.

 

[Bob Nelson 35Whelen]

I have read doing an Ackley improved version of some cases is not always a real world gain.
I considered having it done on a .22-250 or a 7mm-08 simply because my smith has dies and was working on them.

Now, I am seriously considering having a .280ai built for me on a Tikka action.

The round has been standardised I believe and is available

How well do Tikka actions take this conversion? Specifically for the .280ai and any others is the sharp shoulder and feeding an issue?

Any feedback on the .280ai for a mid calibre hunting rifle?

@CBH
Fear not about feeding issue my son
The Tikka feeds from a single stack mag so no stacking issues. The rotary mag and centre feed mags are also good.
It will feed like a newborn baby mate.
Bob

 

[CBH Australia]

Thanks @bruce moulds sounds like you will try talk me into it.
It won’t be a Dingo only gun but I do try get into Dingo country occasionally so they are on the menu. I like the way you think as I have heard good things on the .25-06 and it’s flat trajectory over the years.

Hey @Bob Nelson 35Whelen I might keen to test this idea in a Tikka but occasionally someone says the sharper Ackley shoulders can cause feeding issues..

To unveil the grand plan here is what I am thinking. This will be built as a Hunting rifle, one that if I am reduced to fewer rifles in the future or travelling with One rifle anywhere in Australia or maybe overseas it would be suitable and known.

I’m settled on a Tikka action as I have others and could possibly interchange Tikka accessories with my others if I want to change something up.

Recently I considered a Christensen Arms Ridgeline as the pricing was good fat the time but I looked a few days ago and they jumped up a bit.

It I do this build I’m thinking
Tikka T3 action
Carbon Fibre Stock of Hunting configuration either PSE or Bolly.
Carbon wrapped IBI barrel (reasonably priced)

Overall I think I could build this for a reasonable price and effectively build a Mountain rifle or all purpose hunting rifle.

The main catch is the Carbon wrapped IBI only come in 22” or 26”
IBI are the lowest priced barrels I know of but they don’t do 7mm in straight stainless or it’s not available a truck present.
To date I am hearing these barrels are showing good results.

I’m leaning toward the 26” barrel as it won’t be a high volume shooter so I want to get the best performance I can from the round within reason

 

[Bob Nelson 35Whelen]

Thanks @bruce moulds sounds like you will try talk me into it.
It won’t be a Dingo only gun but I do try get into Dingo country occasionally so they are on the menu. I like the way you think as I have heard good things on the .25-06 and it’s flat trajectory over the years.

Hey @Bob Nelson 35Whelen I might keen to test this idea in a Tikka but occasionally someone says the sharper Ackley shoulders can cause feeding issues..

To unveil the grand plan here is what I am thinking. This will be built as a Hunting rifle, one that if I am reduced to fewer rifles in the future or travelling with One rifle anywhere in Australia or maybe overseas it would be suitable and known.

I’m settled on a Tikka action as I have others and could possibly interchange Tikka accessories with my others if I want to change something up.

Recently I considered a Christensen Arms Ridgeline as the pricing was good fat the time but I looked a few days ago and they jumped up a bit.

It I do this build I’m thinking
Tikka T3 action
Carbon Fibre Stock of Hunting configuration either PSE or Bolly.
Carbon wrapped IBI barrel (reasonably priced)

Overall I think I could build this for a reasonable price and effectively build a Mountain rifle or all purpose hunting rifle.

The main catch is the Carbon wrapped IBI only come in 22” or 26”
IBI are the lowest priced barrels I know of but they don’t do 7mm in straight stainless or it’s not available a truck present.
To date I am hearing these barrels are showing good results.

I’m leaning toward the 26” barrel as it won’t be a high volume shooter so I want to get the best performance I can from the round within reason

@CBH
I think true flight in NZ do a carbon fibre barrel. Flick Von Gruff a PM he can help.
Bob