I was interested in Ackley’s work with the old 94. Apparently he fired a few of his .30-30 AI rounds after removing the breech block and there were no untoward effects. The rounds were held only by the bolt/lever assembly, indicating to POA that not much pressure was transferred to the bolt face. Granted this was not very scientific and he did not do it many times. This was consistent with some of my own experiences when, a while back, I tested a bunch of factory .30-30 ammo in five different rifles, two levers, two bolts, and a single shot. The firing usually produced empties in which the fired primers protruded a few thousandths from the case head. This indicated to me that even these tapered factory rounds were not putting much pressure on the bolt face. In Ackley’s comments on the strength of the 94 action I believe that he was expressing personal conviction based on his experience, and not lying.
Being a Krag fancier, I was also interested in Ackley’s work with old military actions. Krag fanciers, and other bolt action nuts, are often worried that a singular pressure event will shear off the bolt lug(s) and send the bolt back through the shooter’s skull. I don’t have my books where I am now located, but if memory serves, Ackley blew up a Krag action using a load of 50 grains of 2400. This Krag had been rebarreled and chambered for something other than .30-40. Be that as it may, the receiver ring was fractured and the barrel bulged, but the bolt stayed in the gun. Again, not very scientific or quantitative, but it gave me to feel that if my Krag were in good condition and I kept my loads in the appropriate pressure range, I probably would not have to leave the range with a bolt sticking out of an eye socket. So far that has been the case.
Ackley’s published data for his AI cartridges and cartridges of other wildcatter’s have been questioned by members of the shooting press for a long time. True, some of his reported results cannot be duplicated by others, but the AI wildcat philosophy is a good one, and it provides a simple, easily accomplished method of increasing the capacity of a standard case. This increase with the .30-30 AI is really remarkable. In other cases, the gain in performance is quite significant. See, for example, David Ward’s article “The 250 Ackley Improved Works” in Handloader’s Digest, 12th Edn. (1990) page 142. He got 100-gr bullets moving around 3200 fps with a variety of powders. Similar improvements were reported with other bullet weights, but not one figure for breech pressure is given in this article. Similarly, in my reading of Handloader Magazine, I find tables and tables of loads for various cartridges generated by the gurus of that publication, but seldom do I see a measured pressure. All one usually sees is the entry “maximum” in the column next to the velocity when the author feels the load should not be exceeded. But these folks are experts, right? They know how to read primers, sticky extraction, etc., and they always measure case head expansion with a micrometer, don’t they?
I think it is true that Ackley considered the primer to be the weakest link in the pressure chain. A blown primer was then, for him, the main indication of dangerous pressure, and so he often merrily increased powder charges until primers began to blow. Then he backed down and called it maximum. I don’t think he ever recommended a load that he thought would blow a primer in a reader’s gun. You may disagree with that practice and you can say, perhaps rightly, that it is not scientific enough, but that is how he worked. This empirical approach is still used by folks who carefully experiment with rifles and loads and then write about it. I am thankful for Ackley’s work. If you find copies of his two volumes for a reasonable price, buy them.
Last edited by McShooty; February 24, 2013 at 05:14 PM.