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I'm having my son's 7MM-08 chambered for an Ackley Improved. Shooting and reloading is his passion and he thinks it would be "kool", so I figured, what the ****.
So, any of you have a 7MM-08 AI and if so, any favorite loads and data you would like to share?
Please no lectures on the AI conversion. I know all about the cost vs velocity vs fireforming etc., etc. It's already done and now it's time to gather data.

Thanks
Steve
 

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7mm-08 AI

Had one: Did not get it done for me so rechambered to 284 Win.

I just used the top loads for the standard 7X08 and worked from there.

Neal
 

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Steve, does the AI give any feeding problems from the magazine into the chamber?
I was thinking of this conversion on my 7mm08, but a friend has a 308AI and complains that it is not as reliable as the plain 308 when chambering a round from the magazine, so I have put the conversion on ice untill I have more info.
Maybe the experts can shed more light on this potential problem?
 

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The standard 7mm08 has .016" of taper in the body of the case, a 20 degree shoulder and a neck that is one caliber; .284". P.O. Ackley did the shooting world a great service by taking older, heavily tapered rounds, with shallow shoulders and long necks, and "improving" them. Even then, the argument against was problems feeding such "square" cases.

An excellent example would be the .257 Roberts, which originally had over .040" taper, a 20 degree shoulder and .321" long neck. The AI version reduces case taper to .017", sports the classic 40 degree Ackley shoulder, and as a result of that shoulder, retains a neck that is ~.325". The end result is a case with more powder capacity, less bolt thrust and longer case life, with less stretching.

When you consider that the 7mm08 already has minimal body taper and an appropriate length neck, there just isn't much to be gained with an AI modification...which is why what little work he did with the 308 family of cartridges didn't go very far. The classic 7mm Mauser is a far better candidate for the Ackley improvements, as is the .280 Remington, both of which achieved some following in their AI configuration. I just don't see where there is much room for improvement in the 7mm08 case, personally.

Other than that, I would echo the earlier posts about using a middling 7mm08 charge as a starting point for the 7-08 AI, working up as you would for any other wildcat, in half grain increments and watching for signs of pressure and the velocity you want.
 
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