I've not only shot AI's and owned them. I also spend numerous hours sitting with Parker Ackley himself in his shop. In all that time, he never had a huge amount to say about his "improvement" of cartridges.

One thing he did tell me, was that he used test bbls. to check velocities with, many of them 26 to 30" long!!! That means he got MAX V gains for the powder burned!!!!

Nothing is for nothing!!! You just can't get huge V gains with out burning more powder, OR pushing the pressures up!!! You can kid your self into thinking you can, but in the "real" world it just doesn't happen!!!

As was already said, those cartridges like the 30-30 have huge gains because case capacity goes up quite a bit, and also because the 30-30 is "under loaded" to begin with!! Others like 25-06 doesn't gain a huge amount "if" you keep the pressures similar to the factory levels!!

Drilling Man