Re: 30.06 ackley - anyone tried it?
The Gibbs is a true wildcat. The parent case has to be modified in order to work. Best to start with new brass as the shoulder has to be relocated.
The process is simple. Neck up to 338, neck back down to 30 just enough to form a second shoulder on the neck. Size down so that chambering requires firm pressure to close bolt. Using 15 to 17gr of HP38/Win 231 under cream of wheat filled to the base of the neck, fire using any LR Reg. primer. I usually put a piece of paper towel in the neck to keep everything in place.
This will form the brass to 95%. The next full pressure load will create the nice sharp shoulders. Brass life is good and rarely needs trimming. Performance should be similar to the RSAUM with mid weight bullets.
I have found H4350 and CCI BR2 primers to work great with 165gr Hornady SST bullets. Brass has ranged from Fed, Win, and LC69. In my rifle, 3000fps is very accurate and 3100fps is definitely max.
To size, I knock the primers out with a Lee decapping die, then size using a Lee Collet neck die in 308Win and a spacer. Bullets are seated using a Forster BR 308Win die. When the cases get too stiff to chamber, I toss them.
I think you will really like it...