what makes an ackley improved cartridge,such as 25-06 a.i., an ackley improved cartridge? what advantages to they have say over a standard 25-06 or a 257 wby?

Ackley imp. chambers are slighty bigger than the std. chamber. You have a gunsmith "ream out" the std. chamber to either lengthen it, take the body taper out, or both. Then you "fire form" your brassin the new "bigger" chamber. Once that's done, you can now reload "that" brass that now holds more powder to a higher velocity than the standard did.

I spent quite a few hours in Ackleys shop. He was quite a character, and i enjoyed every minute of my time there with him. I still have the 240 Wby. he built for me useing a 700 Rem. action and one of his bbls...

Drilling Man

if done properly the beauty is that you can fire factory ammo in it and still get "reasonable" accuracy in a pinch.. say if you found yourself away from home without any handloaded ammo (that had been fireformed)... most of the ackley variations consisted of taking the shoulder of the shell to 40*and moving the mouth to shoulder vertex back .004 inches as well as removing taper from the body, resulting in, you guessed it, more room for gunpowder...

No expert here but from what I've gathered here is the trend:

Take most of the shells taper out, and increase the shoulder angle. Like said about, this gives more case capacity, but it usually results in longer lasting cases if you're a reloader...and yes the beauty is that you can still fire the "standard" if you're in a pinch or to fireform your factory cases to the A.I chamber.

Although my gunshop is only about 90 miles from Trinidad, Colorado - where P.O. Ackley taught gunsmithing - it is amazing how many gunsmiths in this area don't understand how to set up an Ackley Improved chamber. The bolt must not be able to close on a "go" headspace guage, but should be able to close (with a little umph) on a factory round or a virgin brass case. Before fire forming, the case is only touching the chamber at the juncture of the neck and shoulder. The overall length will shrink when fire forming, and after that there is almost no need for case trimming.

They will typically produce 150 to 200 fps more speed than the parent caliber, and often will need a little slower powder to do so. RL22 has really made the family of Ackley Improved calibers based on the 30/06 come alive. It burns a little slower than H4831, but takes up less space in the case. The .25-06, .270, and .280 Ackley Improved's are all at their best with RL22.

One of the best Ackley Improved's is the .22-250. I have mine "loaded down" to 3800 fps, where I have reloaded a lot of Remington brass over 20 times. Without ever trimming a case. It shoots 1/4"

It's reamed out to a 40 degree shoulder and holds more powder. If you are a reloader, the cases last forever. You should get 100 to 150'/sec increase in velocity in the 25-06. The 257 Weatherby Magnum has no ackley version ( to my limited knowledge) becausethe neck and case have already been jibbered with....so the bottom line is the 25-06 is real close to the Weatherby.The Ackley modification has the biggest bang for the buck in .257, 7mm Mauser and 6.5-'06 calibers. The 25-06 will definately perform better when Acklied. One of the great myths is that the 30'06 Ackley doesn't do much.....oh contrair....I get 150'/sec faster speeds out of mine without extreme loads. You can "hotrod" anything, however the Ackley allows you to increase velocity without going to high chamber pressure thereby increasing barrel life and making your rifle a flatter shooter. That's my 2 pennies. For 100 dollars or so, that's a good cost effectiveupgrade. Regards, Rick.

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