Home Forums Hunting & Shooting Ask The Gunwriters Looking for info on 338-08 Ackley Improved

I know at least 3 members that have this cartridge. I'm interested in any info anyone else might have. Please no negative comments. powdr

I have had two 338-06's and two 338-06 AI's. The improved cartridge gets about 30 fps over the standard. The 338-06 runs about 200 fps slower than a 338 Win. with both using 24" barrels. With 250 grain bullets about 2500 is all you can get out of the improved unless the pressures are higher than SAMMI maximums for cartridges like the 270 Win.

As Rosana Dana use to say on Saturday Night Live...

NEVER MIND...

Sorry there Powdr....

Really haven't ever seen anyone build a 338/08 Ackley....

Guys please read again...338-08 Ackley Improved. powdr

A good mate of mine has one, my Ruger 338 WM is such a better gun in every way and cost about a third of what he paid too, not a negative comment, just the facts.

I thought I responded. Start with Nosler data for 338-06. Is there something you specifically want to know? I have a set of dies if you need dies.

Powdr:

I'm sorry that you aren't getting satisfaction . I personally do not have any experience with that caliber.

Best I can offer is more run of calculations with Quick Load. I'll shoot you a PM in the next few days.

There is published date available on that unique and rare caliber. I'll search around some.

Can you be more specific as to desires?

How much load data ?

Any preferences for bullet weight, velocity, pressure ?

Purpose of loads - game - target or both ?

Hang in there. We will work it out eventually.

Bill Tibbe

powdr,

Start with data for the .338 Federal. Adding powder until getting around 50 fps more velocity than .338 Federal data should be safe.

Apparently my friend Rick is getting old enough that he can't tell the different between a 6 and an 8, maybe because he's logging on the Campfire on a smart phone.

Yeah I misread it as an 06 too

John, from what little I've calculated it looks like I can get more like 70-80 feet more per second. I will use your calculations I've seen several times here but hope for a little more than 50fps. I can see you shaking your now!

Bill, I know the cartridge is listed on Quick Load. I am interested in the 180,200 and 210gr bullets for hogs and deer. 60-65,000psi.Any info you can provide would be appreciated.

RinB and Castle Rock...just an honest mistake. powdr

powdr,

Did you use the 4-to-1 formula with fired brass from your rifle, compared to a fired non-improved case?

John,
I am using an iPad so no excuse there.
Powder,
Sorry, I thought it was an 06.

After having fooled around with a few "improved" cartridges, I bet the total gain will be no more than 25 30 fps. I believe that most of the velocity gains attributed to improved cases are the result of higher pressures.

It depends on how much powder room is gained. When the original cases have a lot of body taper and lots of shoulder compared to the neck, then as much as 100+ fps can be gained, when the improved case is loaded to the same pressure.

But when the case doesn't have much taper or shoulder, very little is gained. The .35 Whelen Ackley Improved is a perfect example. In fact it's probably the AI case that's the biggest waste of time.

The .338 Federal case (which is what we're talking about) doesn't have much taper but does have a little more shoulder than the .35 Whelen. A gain of 80 fps over the .338 Federal with 200-grain bullets at the same pressure is approximately a 3% gain. Since each gain in velocity (again, at the same pressure) requires a gain of approximately 4 times as much in powder room.

This means Ackley Improving would have to gain about 12% in powder space. Since the .308 case holds about 50 grains of powder, this means blowing out the modest shoulder would have to gain about 6 grains in powder room. I sincerely doubt it does. I'd guess it gains maybe 3 grains, hence my guess of an additional 50 fps, at most.

Of course, adding another 5000-10,000 PSI would gain more, which is what most handloaders add to AI rounds.

Yea, that's the real "secret magic" of the AI rounds.

Thanks John and others. I could load 53gr in the 358W case but it was compressed. I think I should be able to load 54-55gr in the improved case. We'll see. John, have you stopped shaking your head yet? powdr

Right now I'm firmly convinced the .338-08 AI will equal the ballistics of the .338 Winchester Magnum with less recoil and finer accuracy.

powdr,

I'm betting the gain wouldn't be much more than the extreme spread in velocity with your current loads. TAC, 8208 and Leverevolution do nice things with the bullet weights you mentioned. I'm more than satisfied with velocity of my 160, 180-185 and 200 grain loads.

Thought of the .338-284? That may safely get you where you want to be. The 338-06 would too. Maybe the 338 RCM. They're pretty cheap right now and you could load them down if wanted/needed.

The .338 Winchester Magnum, oddly enough, will also "equal" the .338 Federal, or any .33 cartridge between the Federal and itself. It's really easy to to load down with consistency and accuracy--and to find brass.

My old .338 only weighs 7-1/2 pounds with scope, and I didn't find it all that obnoxious 15= years ago with full-velocity 250-grain loads--but also used it a lot with 200's at 2650-2900.

OK guys, you realize that loonys pay nooooo attention to rational talk. None, like in zero. powdr

This would be perhaps a 338 Federal to start with? Sounds like me, had a 6.5X55 that worked exceptionally well on deer as it was but, got a 6.5X57 and was able to get the magic 50 to 100fps more. At least if it's a Tikka bullet length if you have the longer mag will not be an issue. It is a looney thing.