is going to Ackley Improved worth it?

[openfire]

I have a beautiful rifle built on a mauser action in .257 roberts.
Would I need to replace to barrel to go AI and is the investment in a quality gunsmith worth the gains ?

[58thecat]

your not gaining much in performance....but if you want/need a wildcat then so be it....reamer...no barrel replacement...the investment in a quality gunsmith is always a must!

[fps plus]

You will gain approx 100-150 FPS
Case stretching is almost non existent.

Down side is getting them to feed reliably. Suggest trying some dummy rounds. Usually requires fiddling with receiver and if not done properly ruins feeding . Once done can’t go back

No need to replace barrel just set back one thread and ream to improved chamber

[brewster29]

The very wise Dean2 would warn you that AI cartridges can have feeding issues that their parent cartridge does not have...something to think about for a small gain of +100-150fps. Oops, I see fps typed faster than me.

If your rifle is any sort of classic piece you will reduce its value by modifying it.

[GWN]

Suggest you don't,

As others have mentioned there is a minimal gain, I recall a couple articles (Kenny Jarrett as I recall) where PO Ackley himself felt the 280 AI was the only one that really was worthwhile,

If you have to have one (I know the feeling as I have a 280 AI) I suggest getting a Remington donor action, generally easy to find and relatively cheap and getting it rebarelled, more money but you wont regret changing your rifle

Whatever you choose good luck and have fun,

[Rackmastr]

I have a 7-08AI and likely the gains aren't 'worth it' but I enjoy it. Its a bit different, the case life is great without the need to trim much at all. A bit of extra ability to load, though currently the rifle is my wife's and loaded down to below 7-08 max loads anyways.

In the end its probably tough to justify being 'worth it' but I'd likely do it again just as a bit of a fun thing to play with.

[David Henry]

Ackley improved alterations that show reasonable gains from what I have experienced are. 250 - 3000 Savage, 7 X 57 Mauser and the 30-30 Winchester, the most noticeable improvement is the longer case life as trimming is all but eliminated when full length sizing. Velocity gains in the three mentioned chamberings can vary significantly depending on barrel length.
I would however caution anyone considering the improved chambering in a classic old rifle that the increase in velocity is offset by the devaluation of a nice old rifle. But that will never stop the hot-rodder's from doing what they do. D.H.

[Mr.Crumbz]

I personally wouldn’t bother, but some people want to squeeze out every FPS possible from their cartridges. If your chasing velocity and want something to do all the power to ya!

[openfire]

Thanks for the great input everyone !
I will not be going forward with it.

[Faststeel]

Originally Posted by David Henry

Ackley improved alterations that show reasonable gains from what I have experienced are. 250 - 3000 Savage, 7 X 57 Mauser and the 30-30 Winchester, the most noticeable improvement is the longer case life as trimming is all but eliminated when full length sizing. Velocity gains in the three mentioned chamberings can vary significantly depending on barrel length.
I would however caution anyone considering the improved chambering in a classic old rifle that the increase in velocity is offset by the devaluation of a nice old rifle. But that will never stop the hot-rodder's from doing what they do. D.H.

Interesting to note the 257 is on a 7x57 parent case.......

[Pioneer2]

The 6mm Rem