Well I got around to loading and shooting some fireformed brass for my 223 Ackley "Walk Around Varminter" (www.rvbprecision.com in the photo album). Here are some observations. First off, the gun shoots increadibly well during fireforming. No groups were over 3/4" and this was with bulk Remington bullets. Loading the fireformed brass with a 50grain Nosler Ballistic Tip bullet and 27 grains of Vit133 the bolt lift is hard and the primers are slightly cratered. This is with Remington nickle plated brass. What is interesting is if I use Winchester headstamped military brass I get extremely hard bolt lift. Why this is interesting is that the Winchester brass has more internal volume than the Remington (Rem brass holds 30.5 grains of water and the Win brass holds 31.8) You would think the Rem brass would show much more pressure. Comments?

While I was fooling around with internal volume, I measured some other cartridges for comparison.
222 Mag = 31.6 grains of water
223 Ackley = 31
223 = 30
22 PPC = 31.1
22BR = 37.9

As you can see, there is very little "improvement" from the standard 223 to the Ackley. It would appear to me that the 222 Mag would be the idea cartridge. You could simply run a 222 Mag Ackley Reamer into any 223 chambered rifle without setting the barrel back and I'm guessing the "improvement" would be about 12%. I have a 223 Contender barrel that Mike Belm rechambered for me in 222 Mag Ackley, but I've never shot it. Guess I'll have to do this and see how it works out. I see an order for a 222 Mag Ackley reamer in my future....

My load development is going as follows. So far I've only used 40 and 50 grain Noslers. I always use moly in varmint (high rate of fire) guns. With any load I've tried the gun is shooting under a half inch. (love those Pac Nor barrels!)

My best groups so far are with 40 gr bullets and 27.5 of vit 133 for a speed of 3700 fps and a SD of 6. Groups averaged in the 3s. Although this is great. I expected to be approaching the 3900 fps mark. I can get 3700 with a 40 grain moly bullet out of my standard 223s.

I found 50 grain bullets work much better with the slower Vit 135. 27grains of Vit 135 under a 50g NBT gives me 3400 fps. The average group is in the high 4s. Again, not bad, but not worth the extra work of the Ackley fireforming and rechambering.

So where does this leave me. Trying more bullets and a few more powders to see if I can edge the velocity up a bit without pressure issues.
Any comments?

When you reloaded the formed brass was it full length or just neck sized? What amount of shoulder set back was induced? I ask becuase I had the same problem with a 30 ackley and all it was was to much set back on the shoulder.

Just neck sized........

RVB,

I find some of this interesting.

My nickle R/P 223Ackley hulls,after forming,sizing and trimmed to 1.745"(length that happens to square up all case mouths,on my particular lot of R/P nickle brass,after forming and sizing),weigh 97.2grs with spent primer in place(decapping pin removed for H20 volume measurements).

When filled with H20,they weigh 129.4grs on the average. That yields 32.2grs on the average,for internal water capacity.

Those same hulls,unformed and trimmed to that same length,also weigh 97.2grs,with spent primer in place(who'da thunk it). However,when filled with H20,weigh 125.1grs. Try as I might,I still get 27.90grs of H2O capacity outta the nickle R/P "regular" 223 hull. "Regular" R/P 223 brass is my preference though,over it's nickeled version,but that is moot within this discussion.

You do the math,as far as figurin' percentage of capacity increase,when going from 27.90grs to 32.2grs.

Anywho,as a 223Ackley Fan,I felt it only fair to toss some real numbers forward in regards to capacity.

Now as far as performance,I can't offer much,except to lean heavily on H-335,R/P hulls and the 40 and 50gr molied V-Max's.

Even in my 20" barreled 223Ackley,the 40's will bust 4000fps,the 50's over 3700fps. My longer barrels,will shade those numbers by only the slightest of margins and I've grown pretty fond of a 20" tube in this particular chambering. Have also grown fond of the 1-12" twist too.

31.5grs of H-335 is my favorite for the moly 40's,the 50's will happily digest 30.0grs of same. That in all my personal 223AI's and those of pards,for a shade over a dozen of them.

I've also grown fond of AA-2200 for forming cases and have also found accuracy to be VERY impressive,during that procedure. It also is of much merit in formed hulls,as my particular lot of 2200 is slower than my H-335(by coincidence)and performs equally well in that role.

Soooo long story short,I've got the 223AI in barrels from 20"- 24" and in multiple twist rates. To date the cartridge has largely retired my remaining .224" centerfire battery,due to it's penchant for both performance and extreme accuracy.

To say it was my favorite 22cal offering,would be a gross understatement. To say it offers nothing over the "regular" 223,is comical in the extreme..................

Hey Big Stick, Thanks! Very helpful....You might want to check out what comment someone made about all of this on the gunsmithing forum.....He certainly has a different view than you and I.

Sorry, the post you want to read is from "Pacos" in the varmint forum........

Everyone is entitled to their very own opinion,I'm often partial to mine(grin).

However,I'm slow to weigh the opinion of someone who has never dabbled firsthand with something. ESPECIALLY,if I've got that same "something" setting in my closet and in more than one configuration.

You can learn more hands on,than you can making wild ass guesses. My preference is to build it first,then comment upon it. Other's preferences vary and some even like to speculate upon that,which they have zero experience.

That is not how I do business..............

The conversion from 223 to 223AI is, like the 257, the 7x57, and the 280, are reasonable one that seems to produce increases in performance out of proportion to what you would expect.

If you want to talk to someone who is very knowledgable about the 223AI you should talk to gunsmith Darrell Holland who does tons of them including his "own" version......however, I think Darrell's own preference is for the 222Magnum-AI.

But the problem with the 222 Mag is the availability of good brass. Remington is all that is available.

I know that there are many who swear by the .223 AI, and I'm not here to knock their favorite. It's a perfectly good cartridge. However, I tend to agree with Hot Core that there is such little difference in the standard and the AI in this cartridge as to be negligible in performance parameters.

I have worked extensively with the .222, .223, and .222 Magnum (the .222 Mag in three different rifles). I can tell you that NONE of the .222 Magnums (all with 23"+ barrels), which have a larger case capacity than the .223 AI, using loads of H-335 exceeding that of most manual maximums, would come close to the 50 gr/3700 fps figure that Big Stick cites for his .223 AI out of a 20" barrel. As with most improved cartridges, much of extra velocity usually comes from the owner's expectations and willingness to increase pressures to achieve those expectations. After all folks, most .22-250's wouldn't do much, if any, better than 3700 fps with a 50 grain bullet out of only a 20" barrel.

Hot Core has a good point that to get a significant case capacity increase from any of the .222-series cases, that you might start with the .222 Magnum and push it's shoulder forward to take advantage of some of it's longer neck length, while blowing the shoulder out and sharpening the shoulder angle. This would of course require some "trickery" when fireforming in order to achieve reliable headspace when starting with stadard brass, but it can be done.

BTW, RVB, I have Sako, Herter's, and Remington brass in for .222 Magnum and don't find any disadvantages at all in the Remingtons as compared to the others. I certainly wouldn't let the fact that only Remington brass is readily available in .222 Mag keep me from using it as the basis of a cartridge.

RVB, you are right! The .222 Magnum is the best of the three cartridges. It is the one that should have survived!

The current Varmint Hunter magazine has a pretty good article on getting the most out of the .222 and .223 cases.

I think the 223 Rem AI would have the advantage of less case trimming. The velocity increase in not enough for me to notice.

http://www.precisionshooting.com/
Click on the June 2003 magazine and see:

"The first cartridges designed by Ackley in the so-called Improved shape simply straightened out the tapered case body, giving the original factory designs a more straight walled dimension and leaving the shoulder angle the same. While this proved to reduce back thrust on the bolt, it still showed some case stretching in the neck and shoulder area that resulted in continued case trimming. When he changed the shoulder to something like 30 degrees the case lengthening slowed and by the time his designs reached 40 degree shoulders, all case lengthening stopped, within reason. It became common to reload those cases 15 � 20 times without having to trim them. Thus, the benefits of the famous Ackley Improved cases became reduced back thrust and elimination of case trimming. Case extraction became easier and more positive and loading pressures could be increased safely, resulting in higher velocities."

Oh no! Not the dreaded "back thrust" or "bolt thrust" myth again! Sorry, but fundamental physics says that bolt thrust is purely a function of area and pressure, and the shape of the case has abosultely nothing to do with it.