Standard cartridge in an Ackley chamber

[Emailabode]

Title pretty much says it all, im just trying to understand things a little bit more and from how i understand it an Ackley improved cartridge just has a steeper shoulder or a more aggressive shoulder and the rest of the case remains relatively unchanged right? so what happens if you put a standard cartridge in an Ackley chamber just out of curiosity

[scope eye]

Nothing will happen not until you fire it anyway, no seriously that is how you make or forum an AI cartridge, is to chamber an non AI cartridge and when you fire it, it forms to the profile of the chamber, the term is called fireforming, you can still shoot with good accuracy while fireforming, you just lose about 10% velocity due to some of the pressure goes toward forming the case, instead of all going towards propelling the round, some purists load solely to fireform, by loading a cartridge with powder and instead of putting a bullet they cap off the cartridge with wax or what ever, that way you can forum without worrying about bullet trajectory, there is a valid argument that it is just as hard on the throats of the barrel, so you might as well enjoy the shooting, hope this helps.

Tanks Dean

[stomp442]

Dean pretty much said it all but the shoulder isn't the only thing that changes. Along with the shoulder it takes most of the case taper out as well.

[scope eye]

On the same note, you cannot full length re size to turn a regular case into an AI, you must fireform it, but you can turn an AI back to non AI by resizing it in a non AI or regular set of dies,. we do this for the glory and because our lives are not complicated enough already. LOL

Tanks Dean

[Emailabode]

That was my hunch although a part of me hoped that you would fire it and leprechauns would pop out of the chamber

[Speedrat1]

It happens..... no gold involved at all though..... sorry

[BillPa]

Title pretty much says it all, im just trying to understand things a little bit more and from how i understand it an Ackley improved cartridge just has a steeper shoulder or a more aggressive shoulder and the rest of the case remains relatively unchanged right? so what happens if you put a standard cartridge in an Ackley chamber just out of curiosity

Vell......speaking strictly rimless bottleneck cartridges, head clearance on the parent is established from the casehead( breach face) to the neck shoulder with a crush fit for firing/forming.



As you can see from my award winning drawing() most the body and shoulder are hanging out in the wild blue yonder! When formed the body taper is reduced and the shoulder angle increased.

Some real stuff.....the parent cartridges smoked to show where they make contact on the junction and the aftermath.


The first two are true improved cartridges, the 22-250 and 250. The third set are wildcats, the 270-08 and it's improved version.

Unfortunately, when the term "Ackley Improved" is thrown around 99.9% automatically think velocity instead of much improved brass life. When loaded to the same level as the parent 10,15 or more firing/loading cycles is normal.

Now ya know!

Bill

[stinkitup]

By straightening the case walls and the 40deg shoulder contribute to less brass movement flowing forward during firing so generally don't need to trim either. I know guys with 20 firings on brass and no issue's. I am hoping my 6.5x55AI brass is the same. So far fireforming is proving the usual, straight forward and accurate.

Ryan

[bsekf]

One of the "Ackley" great attributes is that you can use standard ammo should you run out of "Ackley" reloads. Of course POI will change.

[mattri]

As an aside when forming Ackley or other improved cases it is best to seat the bullets a little long so they get a solid jam against the lands. This prevents the case from jumping when the charge goes off. Also suggested to use a warm load to ensure solid full forming of the brass.

[BillPa]

As an aside when forming Ackley or other improved cases it is best to seat the bullets a little long so they get a solid jam against the lands. This prevents the case from jumping when the charge goes off. Also suggested to use a warm load to ensure solid full forming of the brass.

Re-read my post.

[mattri]

Interesting as well, not picking up what you're putting down though, sorry.

[BillPa]

Interesting as well, not picking up what you're putting down though, sorry.

Maybe this will help. http://www.savageshooters.com/showth...roved-Fireform

[mattri]

Sounds like we're in agreement, more than one way to skin a cat.