I started working up a load for my 223 ackley this past weekend. I got 4 different sources for my min max using a 62 gr barnes ttsx and cfe223. Hodgdons website was the highest at 27 gr which shows a velocity of 3,200 fps. I understand that these numbers are with a 24" 1:12 twist and I am running a 22" 1:8 twist so my numbers will be slightly less. However, at hodgdons max load recommendation I am barely getting 3,000 fps. There were no signs of pressure so I ran some more bullets up by .1 gr each until I hit 28 gr. Although I saw no effects of over pressure I still felt as though I should probably stop becouse I just don't like to push things when it comes to safety. But, even at 28 gr I am only getting 3,108 fps, almost 100 below what hodgdon shows at a grain less. So, what is more important in terms of safety, my chrono numbers or pressure signs in my brass? I am not a speed freak, more of an accuracy freak actually but, when using the barnes bullets I like to get max speed out of them as this produces better bullet performance on the all coppers.
Romad27, I don't have the Ackley version, but in a couple 223s with bullets from 50-75 gr, I've gotten my best results in the way of accuracy and speed from CFE.
I prefer to load up in increments until I find obvious pressure signs, so I have an idea where I am as far as pressure. As others have pointed out, 223 data has a max average pressure upper limit of 55K psi, which is far lower than what bolt actions do with other cartridges. Since yours is Ackley'd, it will require more powder to get up to std 223 pressure, and you can go almost 20% over that (in pressure, not powder charge) and still be within the MAP of other cartridges, such as 22-250 or 270 Win. What I am saying is that you can add more powder. Moar! Let the chronograph and your accuracy decide for you, as long as you see no danger signs.
