I shot my 223A.I.today its a Rem VS rechambered.I was shooting 27.5grns H-335,50 V-MAX.My 10 shot avg was 3805fps,that seems really fast but the gunsmith that chambered it for me said thats about what he gets out of his guns.I was shooting it through a SHOOTING CHRONY master beta,conditions where cloudy calm one hour before sun- set 65 degrees.My cousin also shot his Lazzeroni 308 WARBIRD and got 3900fps avg out of 155 Sierra HPBT .

I use win 748 and get 4040 with a 40 gr Ballistic tip and 3650 fps with a 50 gr BT.

I have shot 31 gr H335, 55 gr Vmax, 223 Rem.

Would I get more velocity if I shot the same load in an AI chamber?

Clark. H335 is not a powder I use, so can't really answer your question there. But, I would say, those cases you showed us look like you are running awful hot. A lot of flatening and cratering of those primers. With the looks of them I would guess you are getting a pretty heavy bolt lift also. I would definitely back off those loads a fair bit. The AI case gives you more capacity so loads that were warmish before would generally be milder in the AI. (as long as all other things remain the same) Also the 40 degree shoulder helps with the brass flow problems associated with warmish loads in the .223. With the looks of those cases you are probably experiencing some of those problems. ...ol blue

STW, Over 3800 with a 50gr bullet seems like quite a bit. I run at about 3650 with a 52gr.(warmish, but pressure signs not bad) It shoots very well right there so see no reason to push it. If your pressure signs are not bad, and you are actually getting this kind of velocity, then great. All guns are different, but the operative words are... if pressure signs are not bad. It is also possible you were getting false readings from your chrono. You could always try it again a different day or maybe someone elses chrono. ...ol blue

Ol Blue,

Left to right:
unfired, extractor groove .329"
28 gr, extractor groove .329", 11% overload
29 gr, extractor groove .329", 15% overload
30 gr, extractor groove .3295", 19% overload
31 gr, extractor groove .3320", 23% overload

Hodgdon website: 223 Rem, H335, 25.3 GR. 55 GR. SPR SP, 2.200", 24" barrel, 3203 fps, 49,300 CUP

Test: Ruger #1, CCI 400 small rifle primers, LC brass once fired processed from Scharch and prepped by me, 55 gr Vmax moly, H335

I am curious about the validity of the Ackley critic's statements that the increased velocity is mostly due to increased pressure. How much more capacity does a 223 AI have over a 223?

I have settled on 30.0grs of H-335 with a moly 50gr V-Max in R/P commercial brass as the load for all of my 223AI's. Barrels are 20",22",23" and 24". Speeds don't differ 50fps with that load,from the longest to shortest tubes. They clip along at 3750-ish fps.

Great cartridge.....................

STW,

I only fired one group at over 3,800 with the 50s in my new .223 Ackley; I stopped there because my group opened up a bit. I didn't feel any excessive pressure signs. Regardless, you can bet the pressures are up there. Based on my findings and the posts of others, I'd consider 3,750 a safe max for all around use. Also, if you can reload at the range, try reloading and firing the same case about 10 times and see if your primer pockets start loosening up. Big Stick seems have extensive experience with this cartridge. Do a search for " 223 Ackley" and see what you get.

Regular 223 cases get hard to rechamber and too loose to hold a primer at ~60k ~ 64k psi per Quickload. That is about 2 grains over max for IMR4895 and H335.

I don't know how to enter the .223 AI parameters in Quickload.

[ 06-09-2003, 18:32: Message edited by: Clark ]

Clark, Yeah, I figured you must be doing some sort of high pressure test. I guess you must know what you are doing, since you are still typing. I am not really sure how much more capacity the AI gives. I have never measured it, but it is some. It is enough that I went to the next slower powder. (went from VV133 in .223 to 135 in the AI) I understand several people use 133 in the AI, and go up a couple of grains from their reg. .223 loads. But slowing it down a bit worked better in my rifle. I think the detractors may be missing the point... When you approach these higher velocities with the regular .223, you are really hammering your cases, and the brass is flowing and not lasting long. On the other hand the .223 AI case achieves these velocities without these problems. At 3650 w/ a 52gr bullet, my primers are not flattened, my bolt lift is easy, the brass is not flowing up into the neck, and sizing is easy. (A couple of guys I know have never full length sized their cases. All they have is a wilson neck die) Now I understand that the shoulder angle has something to do with how the brass reacts under pressure, but to answer your question, all of these things make me beleive that it is not just excessive pressure that delivers the extra fps over the regular .223. I do like it. For whatever reason it does seems to be inherently a very accurate case. (it may just be that a 52 going at 3650 fps makes up for some of that crosswind ), but I tend to think there may be a little more to it than that. Sounds like you need to build an AI so you can do some testing on it. ...ol blue