What are the pros and cons of a standard 338-06 vs. the Ackley version with the 40 degree shoulder. I know dies are readily available for both and the only difference with brass would be the added fire forming step with the Ackley.

Considering a Ruger #1 or a Montana 1999 as I am a lefty and the chance of finding a M70 in 30/06 is slim.

The AI version will near match 338 Win Mag performance. In a bolt gun the 40 deg shoulder may not feed as smooth as the standard. This would be no issue in a single shot. If you build it on a Ruger #1 the AI would be the way to go IMO.

not to mention better brass life and the ability to burn some slower powders due to a better internal burn with the sharper shoulders.

JMJ888

Depends on what you want to use it for but AI’s are known to be pretty finicky about feeding well. My two cents worth is I’d go with the standard version.

The standard 338-06 is also close to the 338 win mag and the AI verson gains a bit more.

The AI series of rounds is way way way overestimated and not worth the effort required to make it work. Performance gains are minimal and other stated gains such as case life have never been proven to me. A standard round in a custom chambered rifle will also have very long case life!

Go the standard version!

quote:

Originally posted by vapodog:
The standard 338-06 is also close to the 338 win mag and the AI verson gains a bit more.

The AI series of rounds is way way way overestimated and not worth the effort required to make it work. Performance gains are minimal and other stated gains such as case life have never been proven to me. A standard round in a custom chambered rifle will also have very long case life!

Go the standard version!

I agree!
Having personally gone the AI route (in other carts) I can say never again. With todays powders the velocity gains are NOT worth the effort and money, unless all that is desired is something different.
The 338-06 is perfect as is. It feeds very smoothly, something far more important than minor velocity gains.

I did a .223 AI on a Rem. 700 PSS. There were a couple reasons, mostly that the leade in the Rem. is long, and it's impossible to seat a bullet close to the lands.

To rechamber, the barrel needs "set back." We replaced the barrel lug with a Holland which locally seems to be favored.

Modest gains in accuracy, modest gains in velocity. I ended up doing neck-turning, weighing cases, bullets, double-weighing charges on a beam scale and digital.

Then I was shooting five-shot groups and swabbing the bore. Checking ambient temp at the bench and putting it into loading notes.

It was taking me 4 hrs to load 50 rds. -- AFTER having sorted the brass, bullets, etc.

Too much work. AND the rechamber actually lowered the re-sale value of the rifle.

I have both volumes of PO Ackley's books. They're copyright 1962. Edition I have is 1992. That's 14 yrs ago, and first ed. is 44 yrs old.

Ackley was "leading edge." But I think with today's modern options, he's become "old school."

Of course I realize that some Ackley improvements are better than others. But mostly it's a lot of fuss and bother I think.

My 338PDK ends up being basically a 338Gibbs. I get 5%+ more capacity than the AI. Unless I just really wanted a wildcat I would go 338-06 and not look back. You get 1% velocity for 4% powder at the same pressure. I've used that case from 243 up to 416. I got 1 for 4. As to the brass not needing to be trimed as often. It gets shorter to begin with when you fireform it. I've not noticed a real gain. No saying others haven't just I've not noticed.

Only thing I've seen the case really do is hide pressure signs. That is why you see so many high velocities quoted. Use a pressure barrel or stain guage and it is back to the 1 for 4.

What I found comparing my 24" to my 338Wmag 22" with 210-225 gr bullets and lighter the velocites would basically be the same. With the 250gr the 338wmag larger capacity would help.

I went thru the same process as likely many do when having built one, and what really sold me on the standard was talking to someone who used/built an AI and the owner was disappointed, he said they rechambered the original AI to std and it gained velocity! No matter what or why, point is the AI was not up to expectations, nor worth the trouble, the guy who told me this owned Buzztail brass-they preformed wildcat brass with hydraulic pressure.

He busted both shoulders on an elk at 370-380 yds, and said the 338-06 w/225 pt is all needed to 400 or so yds.

Mine was so easy to load, neck up brass and shoot-VERY easy, VERY accurate, and if I ever built another would go std.

The AI's are 'sexy looking' but I doubt I will build any as most std ctg do what I need- or wildcats with unchanged shoulders. I do like a few i.e. 250 AI and interested in 6.5 Swede improved, but have not and may never build anything other than the std forms.

Just my .02. I like to keep things simple. Friends neck turn, etc. and spend much more time at the bench than I do, but I enjoy shooting.

My #1 Ruger btw is in 6BR std, no neck turn, pac-nor built, .5 moa or better. Shot .498 for 3 @330 yds last time at range.

get the trigger tuned or replaced, mine is Kepplinger set, highly recommend.

IMHO, T-H-E fame of the Ackley Improved series of cartridges rests on three cases; the factory 257 Roberts and 7x57 Mauser, and the 300H&H. He also got the factories to give us modern improved case designs. Guaranteed, Ackley is the man responsible for Winchester doing the 264, 300, and 338 Win Mags, and Remington's excellent 7mm magnum.

Rich

quote:

the Ackley Improved series of cartridges rests on three cases; the factory 257 Roberts and 7x57 Mauser, and the 300H&H

I'd give him credit for improving the 22 hornet, if, in fact, he actually did that!

To say that improvements in the three mentioned cartridges were of significance is a misrepresentation. All he really did was to load them to the 75,000 PSI the brass was capable of holding in the first place.

Ackley was a third rate gunsmith and a first rate bullshipper.

quote:

Originally posted by Idaho Sharpshooter:
... He also got the factories to give us modern improved case designs. Guaranteed, Ackley is the man responsible for Winchester doing the 264, 300, and 338 Win Mags, and Remington's excellent 7mm magnum....

We can all thank the Genius of Mr. Ackley and his peers for the wonderful Cartridges we have today. Granted, the Handbook For Shooters & Reloaders is indeed "dated" due to the huge increase in Powders we have today. It simply means a person needs to read the wisdom of the `40s-`50s with that time frame in mind.

When you look at the Case Designs of just the ones Rich mentioned, and if you have even a modicum of rifle knowledge, you can see the results of those who went before - with Mr. Ackley's efforts right at the front. Anyone that can't see it really doesn't know beans about firearms.

Of course this was long before it was fashionable to be a complete idiot and "sue" the industry over a Case Design.

his design definitely improves the swede,..mine will run the 140gr a-max to 3000fps while still loading in the "sane" charge weights,..(by this I mean NOT venturing into uncharted territory)

also, the 220swift gains a LOT of case life from the conversion. Yes the cases shrink back some when formed,..but the 40* shoulder virtually all but stops brass flow toward the neck and helps to avoid the "doughnut" at the shoulder/nk junction as well as general thickening of the neck and repeated trimming on heavily tapered cases.

I am always amused at the crowd who takes a moderately tapered case and "improves" it, and wonders why they didn't gain much velocity It is becuase the internal volume was already close to maxed out,..but some still have trouble grasping that fact.

I have a few AI's and like them very much,...one of my favorite aspects is the absolute positive headspacing off of the 40* shoulder,...for match work, .001" closer to or further from the lands makes a difference.