Author Topic: Ackley improved calibers (Read 782 times)

buffermop · « **on:** May 07, 2006, 11:03:29 AM »

What exactly does this mean in relation to handloading certain calibers? :roll:

ButlerFord45 · « **Reply #1 on:** May 07, 2006, 11:43:41 AM »

New dies, new receipes

Castaway · « **Reply #2 on:** May 07, 2006, 12:13:54 PM »

An Ackley Improved cartridge has the shoulder blown forward and the angle steepened. Also the area behind the neck is increased in diameter. This leads to more powder capacity and thus more velocity over the original case. Some cartridges benefit more than others from this modification.

Jim n Iowa · « **Reply #3 on:** May 07, 2006, 01:34:04 PM »

If a person was to chamber for(as example) a 243 to a 243 AI all the 243 dies should work except the full length size die correct?
Jim

skb2706 · « **Reply #4 on:** May 08, 2006, 04:14:12 AM »

....mostly no. Because the sharper shoulder angle and the blown out shoulder of the AI, before you start to size the neck down you would mess up the diameter in the shoulder area. You may be able to seat bullets with the seater die but again the die body may contact the case where you don't want it to.

Ackley chambers reduce body taper......and sharpen the shoulder angle....most are 40 degrees. The body of the case actually ends up being shorter than the parent cartridge although the standard round can be fired by jamming it in the chamber. Once fired the case takes on its new form. I have two Ackley chambers and I get 5-10% more case capacity in each. This will get me about 100-150 fps speed increase.

Don Fischer · « **Reply #5 on:** May 08, 2006, 06:31:25 AM »

I've never reloaded for an Ackley but have read his book's. As I understand it, the design has a tendicity to hide chamber pressure as they reduce bolt thrust. I've read where some people think pressure is greatly reduced. In fact pressure is reduced somewhat due to the larger case capacity but I don't know of any standards published that give working pressure's. Were I to reload for an Ackley case, I'd be pretty conscious of case head expansion. Perhaps pressure would show itself there.

skb2706 · « **Reply #6 on:** May 08, 2006, 08:03:51 AM »

In my 22-250 AI I look at it like horsepower.. I have more avialable if I need it. I went with the AI for reduced bolt thrust, to eliminate case stretch (a big advantage if you load large quaninties) and they look cool.