Home Forums Hunting & Shooting Custom Rifles & Wildcats .223 A.I. (Seriously)

I’ll never understand the hatred toward a chambering AI or otherwise?

There has got to be a reasonable middle ground somewhere.

Maybe we can find it on the next .223AI thread?

I understand, I was once a member of the redline club, too. A hot day, oil in the chamber, etc, can turn a borderline load into an over the top load. A locked up gun can ruin a hunt, and a face full of gas from a pierced primer isn't a good time.

It's fine to load hot, until it's not. But it's your face behind the bolt, load as hot as you want.

So, is 3,000 fps hot in a .223AI with a 75 ELD?

“Magical”.... too [bleep] funny...

Pass me some safety glasses and a 6BRA....

I'm not one to push the edge on speed. For my uses, the standard 223 will work just fine on performance. The reason I love the AI version so much is because I hate trimming brass so much...

+1

A WFT goes a long way towards solving that issue, as does buying 223 brass in bulk for 50 or 60 bucks a thousand, and throwing it away once it needs trimming.

A benefit of cheap brass is that it's no big deal if cases are lost down a prairie dog hole or ejected into a snowbank. Of course, that applies to regular 223 or the Ackley.

Appreciate the pic & info, aalf --interesting as always.

for me, fwiw--AI jobs do reduce trimming which is often a PITA. They can bump you up a notch in velocity in a given case when that "space" between cartridges exists --e.g. particularly in cartridges of the shooter's interest that are held to low SAAMI pressure for some legacy reason.

Those are both two good enough reasons for me as a handloader.

That said, more velocity is a product of more pressure or added capacity. A few grains additional capacity ain't gonna net substantial...but pressure sure can make a difference...:)

I think one reason I'm drawn to the whole A.I. concept is that what would be a warm load in a standard case should be more than reasonable in the A.I. case.
In the .223, right now I'm running 75HPBT's in a 16" AR at around 2700fps at what I'm (admittedly) guessing is somewhere just under 60kpsi. Add 8" of barrel, less bullet in the case (deeper throat, more mag length), bullets with less bearing surface (ELD-M vs. HPBT), it seems to me that adding 300fps would be entirely reasonable without being hot. The A.I. chamber should run at even less pressure.

In other words, while everyone wrings their hands over loading the AI hot, running what would be higher performance loads in a .223 should be running at lower pressures in the improved version.

Funny, you never hear anyone complain about trimming Crapmore brass with it's 30* shoulder.

Yet a 22-204 has a 30* shoulder..........

Trimming is trimming....

Nothing “magical” about the WFTs either. Great tool, but still it’s a step I try to avoid if I can.

Did you run Bean’s load in QL yet?

All the THOUSANDS of guys shooting 22-204’s and I haven’t once heard a complaint about trimming brass.

I trim every chance I get.

Unused case capacity will lower pressure w/same powder in any cartridge--determining pressure for a true comparison is the real challenge. Consider that differences in velocity exist between "identical" barrels.

The "warm" load dropped down a grain in the standard cartridge implementing the longer barrel may prove a better round than the AI with the same warm load in your example. It is guesswork, but it is your dime and experimentation is more rewarding than flattening our asses on the internet.

Potsy,

The flaw in your thinking is that when you run standard .223 loads in the AI case you lose some velocity--the inevitable byproduct of lower pressures in the SLIGHTLY larger capacity AI case.

Here's the deal on the .223 AI: Years ago somebody with a strain-gauge reported that the .223 AI came close to matching .22-250 velocities at the same pressure, apparently due to the magic 40-degree AI shoulder.

Unfortunately, strain-gauge pressures can be inaccurate, for several reasons. Which is why companies that use them check the accuracy of the results with that's called "reference ammo," ammunition provided by the Sporting Arms and Ammunition Manufacturers Institute (SAAMI) that's been cross-checked by several pressure set-ups (including the more precise piezo-electronic system preferred by major powder companies). But there is no reference ammo for non-standard cartridges, so there's no realistic way to check whether .223 AI pressures shown by a strain-gauge are accurate.

Of course, many people claim the .223 such great velocities due to the 40-degree shoulder allowing powder to burn "better" or "more efficiently." But I contacted several piezo labs when working on an article about pressure a few years ago, and NONE had ever seen smaller cases produce the same velocity as larger cases at the SAME pressure, regardless of shoulder and case shape The myth of magic shoulder angles and other case dimensions resulting in "free" velocity is just that, a myth.

Still, this .223 AI "info" got out, and one major rifle company was on the verge of introducing the .223 AI as a factory round--until they had it piezo tested, which proved the strain-gauge info was erroneous.

Yes, the .223 can gain SOME velocity over the standard AI, but the amount of extra powder room is so minimal that it makes very little difference. Instead, the higher velocity mostly occurs because of loading .223 AI ammo to higher pressure--which works because the standard commercial .223's maximum average pressure is inly 55,000 PSI. When the .223 AI is loaded to pressures more like the 5.56 NATO's 62,000 PSI, the .223 AI naturally gains some velocity--but only when powder charges are increased. In pressure, there is no free lunch.

Most .223 AI fans report high velocities because they load according to "pressure signs" such as brass and primer appearance, or stiff bolt lift. The trouble with these is they often don't appear until around 70,000 PSI, which is 5000 PSI higher than any SAAMI commercial cartridge, and high enough to result in problems in hot weather, or in a hot barrel--or due to any other little thing that might increase pressure. Which is why no SAAMI commercial cartridge has a maximum average pressure over 65,000 PSI: It provides a pretty good safety margin.

I've owned a .223 AI, partly to experiment with. But I've also "worked up" loads in the standard .223 that came within 50 fps of .223 AI loads with no "signs" of excess pressure. No doubt the .223 loads were far over 55,000, 62,000 or 65,000 PSI, but they did not show any "pressure signs."

The biggest virtue of the .223 AI is less case-stretching when full-length resized in a die that's set up right.This is standard among AI rounds--but also many newer commercial rounds with sharper shoulders. But the AI only results in significantly more velocity than the standard .223 when loaded to much higher pressure.

If there was 55k data out for the .223AI guys would ignore it just the same as the SAAMI data on the .223

A cure, though unlikely, is a factory 223AI round at higher pressures-- ala Nosler with the 280AI at modern pressure accompanied by published lab data.

May take a bit but over a few decades the figures will take a set in the collective mind...:)

I have been shooting the 223 AI on Rem 700's as a single shot since the late 80's, perhaps a dozen barrels or more. Some barrels are on their third set back that are used on colony varmints. You should see a long barrel 223 ai in action on colony varmints.

N133 with 50g is 3800 out of a 26" barrel

N135 with 55g is 3650

H335 with 50g is 3700+

Benchmark with 50g is 3650+

aa2015 with 50g is 3800

aa2015 and N133 with 40g is 4150

all of the stated velocities is at the accuracy node.

I have been shooting the same IMI brand of brass since 1989 which I believe was made by Lapua.

For a repeater, make life easy, go 22/204

For colony varmints, H335 seals the deal on barrel life with extremes in accuracy with speed, and a 50g V max will make you stand up and shout!

all of the above loads and velocities are standard with may guys that I shoot with...no great surprise in 12-14T barrels with zero freebore.