Is anyone familiar with this round? I've heard it comes close to .257 Weatherby. I think I read somewhere, though, that you cannot simply re-chamber your .25-06 rifle to it, as the AI version is shorter and you have to set back the barrel a turn or two. Can you simple fireform the brass from standard .25-06? (I thought that was a "requirement" of Ackley?) I'm trying to decide whether to have a rifle re-barreled to this version or just stick with the rgular .25-06. Thanks for any input.

The 25-06 AI is a great little round. I had the barrel on mine set back a thread so I could shoot factory loads in it in a pinch. You have to form your brass and that is and extra cost and extra time. The 25-06 AI was the first "wildcat" that I have ever done and found it to be forgiving and fun. Mine shoots damn nice and damn flat. Shot a nice buck this past fall and that's all the proof I need. You'll get another 100 - 200 fps out of it maybe and that may matter once in a while but if you think it will be the holly grail then maybe its not worth the doing. If you want something different, a lot fun, and a marginal improvement in performance then it is worth doing. Just don't forget to be a hunter and turn into a shooter. Been there,done that, and trying to get back to the hunting part of the equation. Good luck! Jason

I have just commenced 25/06 AI number 2, although 25/06 AI number 1 with about 1600 shots down the barrel is still shooting well in the field.

In each rifle I have tested and chronographed the standard 25/06 before having the existing barrel rechambered to the AI with 40 degree shoulder. This way you get an accurate idea of the velocity improvement.

Rifle no 1, is a Sako L579 Action Sporter with 23.5 inch barrel. The Remington 25/06 new brass had a capacity of 67.0 grains, and increased to 71.2 grains after fireforming. In the 25/06 with the Nosler 100 grain BT, 56.0 grains IMR 4831 gave 3324 fps, and in the AI, 60.0 grains of IMR 4831 gave 3554 fps.

Rifle no 2, is built on a Sako L579 Action, with a 24.0 inch Shilen SS barrel. The Remington 25/06 new brass increased from 67.0 to 70.1 grains after fireforming. In the 25/06 58.0 grains of H4831sc gave 3232 fps, and in the AI, 62.0 grains of H4831sc gave 3479 fps.

In fireforming cases in an AI chamber, I use a near maximum/maximum load in the standard case, and seat the bullet to engage the lands. I have found that after firing the cases will reduce in length anywhere between .005 and .020 inches.

In rifle no 1, I have used the Nosler 100 grain BT for about 95% of my hunting, and found that it is a very emphatic killer of medium game (feral goats, pigs, roos, emus, etc) in Australia.

To quote my eldest son after he shot 8 feral goats without a miss; "I swear I will marry this gun someday".

I think very highly of the cartridge myself.

Re-22 is my favorite with the 100gr XLC and it is my meat and taters load clipping along at close to 3600fps.

Having had five "regular" 25-06's prior,I personally could not formulate a reason to build another,in lieu of the Improved version. I think Ackley's version is a more betterer mousetrap.

Your mileage may vary...................

How do you fit an 06 case into a Sako L579 action? The one I have is a strech with the 6.5X257AI I shoot in it. It's really more suitable for 243 &308 cases. Am I missing something?

Pete, You don't, and you are not missing something. I must have been suffering brain fade, as the action used in both rifles was a Sako L61R, not a L579.

About 30 years ago I built a custom 22/250 based on the L579 action, and later had the rifle rebarreled for use as a 22/284, but it certainly would not accomodate a 25/06 length case.
Brian

I have a 25-06AI. It is my favorite rifle hands down. What a shooter. I am always reluctant to print load data. Mine loves IMR 4831. Wouldnt take anything for that gun.
Yotes Inc

I recently rebarreled my 25.06 Ruger to the 25.06 Ackley version with a Shilen SS 24" w/ 1 in 12 twist. It loves the 100 grain Barnes X bullet (uncoated). I am getting groupings under 1/2" for 5 shot groups at 100 yards. It loves IMR4831. It will be my deer rifle this fall.

The .25-06 AI, like its parent, is an excellent cartridge capable of high performance. All things being equal, it will give you a little velocity gain over the standard round, and subsequent reloading will be easier (less case stretch, etc). Unfortunately, much of the velocity gain in improved chambers often comes from increased expectations on the part of the owner, who simply keeps adding powder until he gets the velocities he was hoping for. Increased pressure = increased velocity.

The AI comes "close" to the Weatherby round depending on what you call close. At similar pressures, the Weatherby is going to have a 150-200 fps advantage. Many AI owners will claim (and no doubt achieve) Weatherby velocities, but then you can get Weatherby velocities out of a .250 Savage if you disregard normal pressure limitations.

As far as rechambering, it theoretically SHOULD be as simple as running the AI reamer into the existing chamber. The problem is that factory chambers are almost always grossly oversized to begin with, which means that by the time you go deep enough with the AI reamer to clean up the old chamber, your headspace is uncomfortably long for perinially undersized factory loads. Thus, the need to set the barrel back. On the other hand, if you intend to use nothing other than handloads, your chamber may be any length (and the longer, the more capacity and more velocity potential). You simply have to use a larger case (.270, .30-06) as your starting point and push the .257 neck back only far enough to chamber, thereby headspacing on the "false" shoulder you've created.

Have fun and good luck!