"That data is mostly just inflated BS."
Bingo Graybeard. Much of the "data" that is floating around can be attributed to Ackley himself. In many cases the velocities are very "optimistic" to say the least and many are outright distortions. For about four decades i tried to make AI cartridges,
including .250 AI, .22/.30-30 AI, .270 AI (.250 Savage necked up) and .30-06 AI work for me in rifles. The .22/.30-30 AI was a total success. That rifle would shoot the smallest groups that i ever fired from any rifle. All the other calibers were exercises in futility.
"The single biggest problem with the AI cases one and all is the almost total lack of pressure tested data."
Absolutely correct. Do not think that Ackley ever pressure tested anything. Using a 150 grain Sierra BT bullet and a heavier
than recommended load of IMR 3031, that has proved safe in one of my .30-06s, i can equal or surpass anything that i was ever to work up for the .30-06 AI. No, that load has not been pressure tested either but it shows none of the high pressure signs that we watch out for.
I think if I had that much trouble I would have quit on the first one.
"That data is mostly inflated BS." This statement was used the first time in reference to 300+ vel. gain of a 243AI as opposed to a std. 243. Is that what you are in reference too? To me, that number seems high to me as well, considering the 243 does not have much taper, although I have no experience with the 243AI. I haven't studied this round much.
I know my data isn't inflated & as luck would have runs pretty close to the numbers in the Sierra V edition for the 25-06AI & 30-06AI. In reference
to newer, slower powders Sierra says "With these, the 25-06 Improved has started to realize it's true potential." They show a 200fps gain with a 75gr. bullet & a 100 fps gain with a 117, both with 26" tubes. Soooo, I am very much in line with a 125fps gain with a 125gr. Wildcat & RL25, the slower powder wakes up with this even heavier bullet, just what I would expect.
The man that wrote the text about the 30-06AI was not too crazy about it. They mentioned that the straight wall can mask pressure for a while.
Overloading was mentioned as well & that is true & goes back to what I said about the extra care & case life. Also, checking you case head exp. & as JudeinPa mentioned the chrony reading (no reason not to have a chrony now) & if you use your brain & are experienced, no problem. The guy in the text said 40-50FPS increase but the data shows the 30-06 & 30-06AI test guns to be 26" Savages & the AI is 100fps faster with the 150 & 180 & 200fps faster with the 190 grain. How bout that! Cartridges of the World 9th Edition states concerning the 30-06AI "With the proper
POWDER, it will add a little OVER 100 fps muzzle velocity to any bullet weight". Well, that sounds familiar, I get a 100fps gain, not too out of the ordinary at all I suppose & what I have seen from several sources.
Wow, see what Sierra says about the 6mmRemAI, yea baby!!! Expect better than a round like the 243AI because the 6mmRem has more taper.
Sierra says the following: "After fireforming, the improved case offers an increase of about 11% over the original design. This is a fairly substantial increase & provides a significant boost in velocity over the original 6mm Remington." Their data shows a 300 fps gain, though a good 100fps could be the diff. tube length. Goes back to what I said earlier about some cases gain more than others.
Well, what about the 30-30 AI? I said it has given me 200 fps with my best load. Sam Fadala claims 300fps for his Winchesters, a 100fps over what
it has done for me, but I would not call him a liar just yet & I was not there. Cartridges Of The World 9th Edition says the following : "Many hunters
have wished that the 30-30 had a little more oomph. The 30-30 Improved does just that by providing an additional 200-300 fps WITHIN THE
PRESSURE LIMITS OF THE STANDARD MODEL 94 WINCHESTER ACTION." Quite a statement there!!! Sooo, my results of 200fps is on the LOW
end of what Cart. of the W. said to expect. Someone said I could not get there without too high pressures. Go tell that to Cartridges Of The World, not me!!!
So I guess my data being in line with Sierra & Cart. of the World is quite reasonable after all.
Quote & requote: "The single biggest problem with the AI cases one and all is the almost total lack of pressure tested data".
Well, OK, but then this happened.
Quote: Absolutely correct. Do not think that Ackley ever pressure tested anything. Using a 150 grain Sierra BT bullet and a heavier than
recommended load of 3031, that has proved safe in one of my 30-06's, I can equal or surpass anything that I was ever to work up for the 30-06AI. No, that load has not been pressure tested either but it shows none of the pressure signs that we watch out for."
So, does this mean the following:
1. It is bad that AI loads aren't pressure tested, but OK with std. loads.
2. Be afraid to say anything about an AI load (I won't anyway) because it could get dangerous & take out a couple of city blocks, but freely mention
we are over the book in a powder charge & it is OK because it is a std. cartridge & after all the pressure signs "we would watch out for" did not show up, even though we say at other times these indicators are unreliable.
3. AI's are no good because someone tried them & they did not work for him.
4. We should say on one hand that AI's with their increased powder space isn't magic because it is a small increase, but we can say that a std. cartridge is just as fast or what to heck faster with less powder space?
NAY, I DON'T THINK SO!!
alsaqr, the fact that the AI's you tried did not work for you mean only ONE thing, they did not work for you. The fact that some AI's worked for me mean only one thing, they worked for me. That even happens with factory cartridges that some load for. Sometimes, you just can't get to the velocity you are supposed to. That only means you can't do it with that set-up, it happens. But no need trying to tell Sierra it won't work, they have the goods.
I would like to know why a std. cart, in this case a 30-06 would be no slower, possibly faster than the AI with more powder space. Is there any other 30 cal where this would happen? 308vs30-06, 30-06vs300H&H, 300H&Hvs300WM. Reminds me of some that think a 300WSM is faster than a 300WM when loaded to same pressures. I would like for you to explain how this could be please concerning the '06.