Recently I met someone at a shooting range who was shooting a .30-06 Ackley Improved. I compared his cartridges to mine and noticed the difference in the angle of the shoulder.

He claimed that the 30-06 A.I. is a much flatter shooting cartridge. He also told me that he fireformed his cases from ordinary 30-06 brass, which sounds alright, but he also told me he was using normal hunting loads for fireforming, within the min-max range stated by the powder manufacturor.

My questions are:
1. Is there a significant difference in performance between the 30-06 SPRF. and the A.I.version?

2. Is it safe to fireform brass the way he does it?

3. Would a sound and solid 98 based rifle be strong enough for A.I. improved rounds?

You’ll pick up about 100fps over the standard 06 with any bullet weight...and you will have a slight increase in case capacity.

Everyone I have known that has gone that route has fireformed their cases in the new chambers without any problems.

quote:

2. Is it safe to fireform brass the way he does it?

3. Would a sound and solid 98 based rifle be strong enough for A.I. improved rounds?

-----------------------------------

1. If the rifle is properly chambered and headspaced when being "improved", it is definitely safe to fire-form brass that way. In fact, the AI chamber is designed for that method of fire-forming.

2. If a rifle is safe for the 8x57 Mauser cartridge, then it should easily be safe for the .30-06 AI, again assuming a "given" is proper chambering and headspacing. I have had numerous Mauser 98 rifles with 8m/m-'06 Ackley Improved chambers and never had a lick of trouble with any of them.

The most frequent problem I have seen with AI chambered rifles is that the owners ASSUME they now have a .300 RUM equivalent and load them to much higher pressures than they would ever consider loading in their standard '06s. AI rifles MAY be safely loaded to slightly higher pressures than the standard '06 IF there is any truth to the old belief that straighter case walls grip the chamber walls better than tapered case walls do.

But, the real advantage to my way of thinking is that you can use slightly more powder of a slightly slower burning rate to get a longer burn/dwell time where the pressure is at or approximating the original cartridge pressures, So, with the same pressure for a slightly longer period of time, you get a slightly increased velocity without a higher "peak" pressure.

If a shooter wants more than that, I'd suggest he get a still bigger cartridge.

Based on my experience with the AI, Gibbs and my own wildcats over the last 20+ years assuming the same pressure a 100FPS increase for an 30-06 is on the high side. You increase the powder charge 5-6% this will give you a 1.25-1.5% increase in velocity So if you assume 2900 for the 06 you get an increase of about 40-50 FPS. People often quote huge gains. But only because they are increasing the pressure. Over pressure a 30-06 you get the same velocity. 100FPS in a 165 30-06 will give you .4" less drop at 300 yds. 50FPS would be half that.

The purpose of the AI is to allow factory ammo to be fired in the chamber. So using normal 30-06 ammo to fireform is perfectly fine. Both the 30-06 and AI are loaded to the same pressure.

quote:

Originally posted by ramrod340:
Based on my experience with the AI, Gibbs and my own wildcats over the last 20+ years assuming the same pressure a 100FPS increase for an 30-06 is on the high side. You increase the powder charge 5-6% this will give you a 1.25-1.5% increase in velocity So if you assume 2900 for the 06 you get an increase of about 40-50 FPS. People often quote huge gains. But only because they are increasing the pressure. Over pressure a 30-06 you get the same velocity. 100FPS in a 165 30-06 will give you .4" less drop at 300 yds. 50FPS would be half that.

The purpose of the AI is to allow factory ammo to be fired in the chamber. So using normal 30-06 ammo to fireform is perfectly fine. Both the 30-06 and AI are loaded to the same pressure.

Not being a handloader I will differ to your knowledge and experience on the matter.

My own thought's about the AI version is that if the standard 30-06 isn't enough you're going to need one heck of a lot more than the AI version to get the job done. Most AI'ers I know are grossly optimistic about their pets... a guy like Ramrod340 is the exception not the rule!

I just built a 30-06 in AI on a Montana action
(correction...am completeing the rifle).

The 'smith is going to put some iron sights on it this next week.

I shoot this and other AI cartridges for a reason: I feel this design allows for a greater margin of safety when shooting at the upper edges of "safe" pressures.
This cartridge will be loaded in the 60 to 63 KPSI range.
And yes, I can certainly reload the standard 30-06 like that too (and get similar velocities).

I am careful about doing this, and those pressures are well within the tolerances for modern steel in a well made gun. I see the minimum taper and sharp shoulder as just a small added margin of protection for me.

BTW, this will probably be a one-load gun: TSX 165 grain bullet at just over 3000 fps.
Not very exciting by high power standards, but I am hoping it will look pretty in the stock being made for it

Garrett

quote:

1. Is there a significant difference in performance between the 30-06 SPRF. and the A.I.version?

NO...

quote:

2. Is it safe to fireform brass the way he does it?

Yes...shoot factory loaded .30-06 in the AI chamber if it's done right.

quote:

3. Would a sound and solid 98 based rifle be strong enough for A.I. improved rounds?

Any action suited to the .30-06 will also handle the AI version.....this certainly includes the '98 mauser

this quote bt Brad hits the nail squarely on the head

quote:

My own thought's about the AI version is that if the standard 30-06 isn't enough you're going to need one heck of a lot more than the AI version to get the job done. Most AI'ers I know are grossly optimistic about their pets... a guy like Ramrod340 is the exception not the rule!

Garrett,
I feel the same way about the case holding pressure better. I also feel the fact that it doesn't show the normal changes is why people take the load so high and get the velocities they claim.

My own 280 based wildcat is like an Improved Gibbs. Less body taper than the AI with the shoulder moved to give a neck of .28 in 7mm.It more than doubles the addition capacity given by the AI. I did some strain guage work with it years ago. I was able to duplicate some of the claims I've seen for the AI but it took pressures around 70,000. I also saw that I was over 70,000 before I saw normal signs and that it was over 75,000 before the primer let go.

Brad thanks for your comment.

Reindeer if a normal 30-06 won't get it done then get a magnum.

If you look at the loading manuels that list both factory and AI you will see only a few FPS gain.

PO Ackley made his fame before chronographs were in wide use. They have pretty much deflated his claims and I suspect that they will fade away in time.

I had one and say it isn't worth doing.

the ackley improving of cartridges I believe has more benefit when you are trying to make a cartridge more efficient rather than just get it to perform better. Any rifle that will handle a 06ai will handle a 308 norma for instance without too much work, and although brass is more expensive it is going to be a more streamlined loading process since no fireforming to worry about.

Your questions
1. No, not significant, and in my opinion not worth the effort. The 35 whelen AI, the 257 Rob ai and 7x57 ai are all good cartridges and efficient. There I can see it (by the way people in my family have all of those or have had at some point and they have been chrono'd and shot enough to find out that they are great cartridges).

2. I always shot standard loads to fireform, using it as additional practice time. Some of the loads would still shoot very accurately just to a lower point of impact usually.

3. Any 98 with proper heat treating and any of the right springfields etc. should be perfectly fine for it. as mentioned, since you shouldn't be loading it any hotter than a standard 06 then any rifle originally chambered for the 06 should be fine as long as you aren't stoking it up.

My advice though, keep the 06 and get a 300 magnum of some sort if you need it or sell the 06 and replace it with one.

Red

Many cartridges benefit from the conversion,..and many do not. The 30-06 is one of those that does NOT. The 257rbts, and 6.5x55 etc do gain more. If one thinks they can load to magnum velocities,.they will soon find that it can be done, but the cases won't last more than a few firings before primer pockets are toasted.

I like the ackley for it's positive headspacing and case life when kept to sane pressure levels. Mine all shoot extremely well and as long as the barrel is being chambered anyway,..go to the AI if it is a caliber that will notice the change. I would not go to the AI in a 30-06. MHO.

several months ago we beat the AI issue to death here and tempers flared badly...some just don't want to hear that their "baby" is not what they think it is.....Personally I don't care but for those that want to build one based on reports that they are slicker than a former president it makes sense to get the facts out there.

There was actually one guy that posted that his .257 Roberts AI shot faster than the published velocity for the .257 Weatherby. Hey...if that's what you want to believe....have at it.

In the end it was pretty much agreed that if one increases case capacity X% then the velocity increase would be about 1/4 X%. In other words if converting a case such that the powder increase was 10% then he could expect to increase velocity 2.5%.....a 3000'/sec round would gain 75'/sec at the same pressure. This is entirely within reason and experience with those that use pressure barrels to check loads.

In fact very few AI cartridges actually make a 10% increase in capacity and the .30-06 is among them

A quote from Hornady's handbook about the .30-06 improved..."But our .30-06 Improved did not live up to better performance expectations; it only succeeded in using more powder to reach the same velocities possible with the standard .30-06"

Illogical as it seems...this is published in their manual. Take it for what it's worth.

Ramrod340, you're welcome! It's refreshing to find an objective reporter...

This is a chance for us to learn somthing.
Why will a Ackley improved case take more
pressure than a standard case?. I would seem
that the case head is still the weak point.
Good Luck!

The Ackley case provides more velocity because of slightly increased case capacity, plus many Ackley fans load 'em to the gills, beyond prudent pressure levels. Remember, no SAMMI specs exist for these cartridges, and if these cartridges were all that they're cracked up to be, and major ammo companies would have picked them up a long time ago.

I've been around a number of 30-06 Ackley Improved rifles, and I've chronographed some of them at the range. Most of them have produced about 2800-2850 fps. with 180 gr. bullets, and pressures were right at the top. Quite honestly, I don't think all of the fire-forming and related hyjinxs are worth the trouble.

Personally, I've never had any trouble getting 2750-2800 fps. out of the good ol' standard 30-06 with 180s.....

Quite honestly, P.O. Ackley was not an experinced hunter. He founded a gunsmithing school, but he was a third-rate riflesmith, an experimentor, and a theorist. I think his cartridges were and are an impractical waste of time. If he would have hunted more, he would have seen this for himself, and I think he could have better spent his time in other ways......

AD

Hawkins
I simply think that the AI case due to the fact that it has been fireformed to the chamber does not show pressure signs as much as a factory case. I've found that the AI case will let a primer go at about the same pressure as the factory. Based on strain guage somewhere in the 70-75000 range. The AI might be a touch higher if the rechamber is real tight in the head area.

The lack of taper might also allow the case to grip a little better forming a better seal and reducing the bolt trust.

Many AI shooters are operating with a false sense of security. In my opinion the AI should not be loaded to any higher pressure than the factory round. That said I see no reason that a 280, 30-06, etc could not be loaded to the higher standard pressures of a 270 or 25-06. If a person did that to begin with he would capture the majority of the AI gain anyway.

Allen Day,

You are very wrong about Ackley not being an experienced hunter (although I acknowledge that there is no certification as to what "experienced" means).

Each year he closed his shop to hunt for up to a month at a time.
He did extensive field testing of high velocity (over 4000 fps) cartridges on sheep, goat, bear, deer and elk.

It's one thing to disagree with his gunsmithing.... but most of us won't have the opportunity to hunt as much as he did.

Garrett

Somewhere in my books and notes I have a list of Ackley improved cartridges. Ackley had these worked out to the most succesful of his improved cartridges, those which had the biggest improvement, worked out in percentages of improvement.

A lot of folks on this board like to bang on PO, but he wasn't a fool by any means. He knew some of the improved cartridges worked well and others were marginal at best. If someone has this list a post would be appreciated and settle some of the dust created by these threads.

As I recall his best improved cartridges hold little interst nowdays. I seem to remember the 30-30, and the 250-3000 being the most gain. The 30-06, and even the 280 didn't get near the preformance increase, and PO was aware of these and felt these were not really successful.

To the nay sayers of Ackley cartridges, why he is being criticised so many years after his death, for a conclusion he reached and published over 40 years ago, I just don't see the point. He was fully aware that some of the cartridges were margianl improvements, further why his worst improved cartridges are today are the most popular only leads to my confusion. To the fans of Ackley cartridges all I can say is there are some very good improved cartridges, and there were some that are not much more than a waste of time in the end, all of these improved cartridges were not created equal.

For me the best of his improved cartridges are the 257 Roberts and the 250-3000. Another that deserves honorable mention is the 30-30, but the modern 307 Winchester has addressed all the gains with a factory cartridge which makes a 30-30 improved DOA in my book.

A balnaced view of PO Ackley lies somewhere between these to extremes, to the disciples I will remind you he was a man and put his pants on just like I do; one leg at a time. To the other camp he really liked teaching, experimenting and writting about his experiments, that was his biggest contribution to the shooting sports.

In the real world, there's a whole slew of guys who have hunted a whole lot more than old P.O. did. If Mr. Ackley had ever hunted far from home, sooner of later he would have run into a situation that would have demonstrated what a logistical mindblower he had created for himself with his wildcats, and I've lived through this stuff myself, the saving grace being that I was shooting standard factory chamberings, not off-beat cartridges.

When the only source of ammo resupply is back at your loading bench, some 10,000 miles away (or even 500), you've created for yourself a boondoggle. Besides that, you're fire-forming cases, wasting bullets, powder, and time -- and for what, another 100 fps.? There's nothing smart or efficient about that, let alone the fact that resale value of wildcat-chambered rifles is abysmal, the headstamps on the cases don't match up, etc. In my opinion the quest for wildcats usually follows a misplaced set of priorities and more than a few naive dreams......

Jack O'Connor summed it up pretty well in 'The Hunting Rifles', page 8: "The writer who has had a hand in the development of a wildcat cartridge is about as objective as the proud grandfather is about a two-year-old grandson who was named after him. Did anyone ever hear of a wildcat cartridge that didn't shoot into less than an inch and kill like a bolt of lightning?"

Lots of riflemakers create wildcats under their own name, listing amoung the advantages greater accuracy and efficiency, miraculously better killing power, etc. Usually the claims amount to just so much marketing B.S., and only result in the gullible client wasting his valuable time and money, increasing his hassle ratio, minimizing the resale value of his rifle, and decreasing any logistical advantage he would have enjoyed by sticking to standard factory cartridges......

AD

quote:

Jack O'Connor summed it up pretty well in 'The Hunting Rifles', page 8: "The writer who has had a hand in the development of a wildcat cartridge is about as objective as the proud grandfather is about a two-year-old grabdson who was named after him. Did anyone ever hear of a wildcat cartridge that didn't shoot into less than an inch and kill like a bolt of lightning?"

Allen, so true. What is even more confusing in this mix is that the grandfather in this case was less zealous than the followers.

quote:

There was actually one guy that posted that his .257 Roberts AI shot faster than the published velocity for the .257 Weatherby. Hey...if that's what you want to believe....have at it.

Vapodog,
I believe i'm the the guy you are referring to. My claimed velocity was exactly what the chronograph(Oehler)read. The load came out of Speer's #8 manual and in my rifle did exactly as stated, 3,607 fps, 57gr. Norma MRP, 100gr. Speer spitzer in Winchester cases,CCI 200. This rifle has a Shilen polygon bbl, 27.5" and this ain't a truck driver story.
Stepchild

A person, laboratory or armory does not have to hunt at all to develop a cartridge. Hunting has nothing at all to do with it. It's time to dispell this notion.

In general the improved rimless cartridges work fine if the headspacing is done right to get a crush fit on the parent cartridge. This requires setting the barrel back unless it's a new one. The net of this is that the barrel may not fit the stock as well and iron sights will have to be lined up again. All in all its a moot gain but on the other hand the sharp shouldered fireformed case at least looks cool.

Lysle Kilbourn was the first to do this on rimless cartridges and his creations were very good. Later Ackley, Miller and others led us down the wrong track by blowing out belted cases and those are poor designs.

I have a few of the so called improved chamberings and wish that they were not odd balls. The 30-06 that I had "improved" gained a little velocity. Is it worth it? No it's not in terms of results but it was fun to do and the rifle still shoots quite well.

[QUOTE]Originally posted by allen day:
Quite honestly, P.O. Ackley was not an experinced hunter. He founded a gunsmithing school, but he was a third-rate riflesmith, an experimentor, and a theorist. I think his cartridges were and are an impractical waste of time. If he would have hunted more, he would have seen this for himself, and I think he could have better spent his time in other ways......

A third rate riflesmith? If he would have hunted more? I think you should get a copy of "Handbook for shooters and reloaders" and some of Mr. Ackley's other publications and educate yourself. Anyone who speaks ill of St. Parker is an unclean heathen!

The reason many like the 257, 250-3000 got the huge jump in velocity is because the standard factory loading was in the 54,000 range. Then you jump to 60-65,000 you are going to get a big gain. A factory 270 is loaded to 63000+ so no gain.

Based on my experience with a 257AI a 25-06 and my own 25-06 Gibbs Improved with up to a 28" barrel. A true 3600FPS with a 100gr in a 257AI isn't done at normal accepted prressure.

I don't have a Speer #8 but my Speer #9 doesn't list MRP if I assume N205 is MRP it lists 54 max at 3348. They only list 56grs in the 25-06. The #9 doesn't even show a 257 Wby load making 3600FPS.

Ramrod340,
The powder(Speers data) is in fact N 205 and not MRP. Speers test rifle is shown acheiving 3,410 with a 22" bbl using 57gr. N 205, 100gr bullet. I don't have any pressure test equipment but i'm using the same cases that I bought in the 70's when the rifle was first built, so I don't guess i'm hurting them too badly.

Stepchild

The fact that virtually all new factory cartridges are now minimum taper with sharp shoulders speaks volumes about the efficacy of the design.

This design simply allows for the better management of higher pressures.

If you don't plan to shoot full power loads (that remain within safe parameters), it's not necessary.

Garrett

quote:

Originally posted by stepchild 2:

quote:

There was actually one guy that posted that his .257 Roberts AI shot faster than the published velocity for the .257 Weatherby. Hey...if that's what you want to believe....have at it.

Vapodog,
I believe i'm the the guy you are referring to. My claimed velocity was exactly what the chronograph(Oehler)read. The load came out of Speer's #8 manual and in my rifle did exactly as stated, 3,607 fps, 57gr. Norma MRP, 100gr. Speer spitzer in Winchester cases,CCI 200. This rifle has a Shilen polygon bbl, 27.5" and this ain't a truck driver story.
Stepchild

It makes absolutely no difference to me whatever.....but for those that might want to reproduce such a gun/chambering the data speaks for itself.

Stepchild2

Like I said I have no clue what is in the #8 manual. The #9 lists 54 as max with a velocity of 3348 with a 24". I didn't say you weren't getting the velocity you claim. I said in my opinion it can't be reached at normal pressure. Buy all means shoot what you want.

While I value my opinion I've found that it and a $$ or two will buy you a cup of coffee.

What I don't want to see is some hurting themselves or others trying to get 257 WBY velocity from a 257AI.

Again this is my opinion. Many people claim that "their rifle give velocities high than factory ammo claims or even the posting is the loading manuals" This happens because their chamber and barrel is to the tighter side of standard. This gives them higher pressure for any given powder charge. The only way a given charge in the same case in different rifles will give higher velolcity is higher pressure.

Thank you all for your answers and comments on this issue.

The thought had passed my mind to 'upgrade'my 30-06 into a AI.

Since it is a sub MOA rifle at present and there is not much to gain, but the risk to loose accuracy, it will stay what it is, 30-06 SPRF!

I read a lot on the net about gunsmithing and reloading and there is always the question 'what if?'