Thread: 30-06 Akley improved load development

Now if you had brought a 300 wsm long ago you be slinging your 165 grners at 3250 your 200 gr pills at 2800-2900 scoring records at 1k and saved a huge amount of dosh. Say no more

Greetings @dannyb,
I remembered that there was an article in Handloader and dug it out. Gil Sengel did an in depth article in 1986 in issue 123 of Handloader Mag. He worked up loads using case head expansion to estimate pressure for both the .30-06 and its AI cousin. He used the same barrel and throat to reduce variation. One of the powders used was IMR4350 which is very close in speed to current AR2209. The increase in velocity for the AI was modest generally 50 fps or less which is about what you would expect from the small increase in case capacity.
For the 165 grain he loaded 60.5 grains of IMR4350 for 2,955 fps and for the 180 grain 59.5 grains of IMR4350 for 2,820 fps.
Regards Grandpamac.

Bob Jourdan (creator of the 6.5x55 BJ AI), the late USA gun writer did an excellent article on Ackley Improved cartridges in the Precision Shooter magazine. I have a copy of that issue somewhere which I must dig out.
He did extensive testing and, along with the article, created a chart of "Ackley" Improved cartridges. Keep in mind that Ackley didn't create all of the cartridges claiming the AI suffix. He was long dead for some of them. The 6.5x55 BJ AI is obviously one of them.
The chart lists many cartridges that have disappeared with time.
His rule of thumb was anything with around only 6% improvement wasn't viable to fiddle with.
For many years I have had Jourdon's 6.5 Swede Improved. It offers substantial improvement over the standard chambering. Having said that, I wouldn't bother with another one once the barrel is toast.

As previously mentioned I'm happy to have one for the simple fact it's different, the mighty 30 06 is already a good cartridge and even if there was no increase in velocity there are other benefits to an Ackley case (they don't require nearly as much trimming once fire formed.
When this barrel is toast I'd like to think if I still own it I'd consider 280AI or even 7mm BC if it turns out to be viable....I've got plenty of time before that's a concern.

Anyway update as promised.... a mostly frustrating day at the range with only my Sako blade load data being of any use.
There appears to be promise in the sako blade as far as accuracy is concerned with most groups shot being less than 1" (granted not a big enough data sample to make any claims) I was only shooting 2 shots at each charge weight just to check velocity.

The first was a 3 shot group as I loaded an extra round for confirmation of my bore sighting 1/2" group SD of 8.6fps

Second group SD of 24.7fps

Third group SD of 11.3fps

Fourth group SD of 1fps (2shots touching)

Fifth group SD of 9.8fps

The forth charge weight was 59gn of 2209 and gave a velocity of 2896fps I was initially disappointed as I was hoping for 3000fps.
However after coming home and reviewing sako factory loaded ammo data I am content that there may be a load worth investigating, I would need to load up 10 or even 20 and see what the true accuracy looked like but given all but the very highest charge weight were sub 1" or even sub .5" and all but 1 load showed fantastic SD consistency.

59gn group pictured (need to load a bunch of these and get a decent data set



Here is the specs from the factory loaded Sako ammo, I've managed to get over 100fps more which isn't to bad.

Now for the frustrating part of the day....
My berger and nbt data is absolutely wasted as due to a cock up measuring my jam my projectiles were seated to long and I couldn't even close the bolt on them, I've decided I'm not going to pursue the bergers but I have re measured my jam with the nbts and loaded a new charge ladder that I hope to shoot tomorrow with them.

The only issue with the sako blade is that it's recommended to keep minimum impact velocity to 1800fps and even with the 100fps gain over factory that limits this load to 300yards which falls outside of what I'm trying to achieve.

https://www.nzhuntingandshooting.co....ead-es-111291/

Just sayin' - re: SD

Interested to see where it ends up with some full testing

Originally Posted by gimp

https://www.nzhuntingandshooting.co....ead-es-111291/

Just sayin' - re: SD

Interested to see where it ends up with some full testing

Fully aware I need a lot more data, today was only about checking velocity and ruling out anything that was horrendous (ie a 3" group will never be a viable load for what I want, and will never be better than a 3" group no matter how many rounds you put into it)

It would be interesting to see you shoot those same groups again and come back with results.

Second group SD of 24.7fps

Third group SD of 11.3fps

Fourth group SD of 1fps (2shots touching)

Fifth group SD of 9.8fps

Originally Posted by McNotty

It would be interesting to see you shoot those same groups again and come back with results.

Second group SD of 24.7fps

Third group SD of 11.3fps

Fourth group SD of 1fps (2shots touching)

Fifth group SD of 9.8fps

I agree, but in reality not a lot of point pursuing this load as it's only a 300yd load at best and not really what my goal is. If the NBT's show promise I'll shoot enough to get a valuable data set from them, if not I'll load up some 178gn eldm's that I have a known load for and be happy.

I have a std .30/06 with a match 24” Madco barrel. 58.5 of 09 with a 165 Nosler BT is my go to load. 2930 fps.
The swap to the 165 accubond only needs 10 mm of left for the same point of aim at 100m. Same velocity and BC.


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Originally Posted by Dicko

I have a std .30/06 with a match 24” Madco barrel. 58.5 of 09 with a 165 Nosler BT is my go to load. 2930 fps.
The swap to the 165 accubond only needs 10 mm of left for the same point of aim at 100m. Same velocity and BC.


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Wow that's great velocity I would suggest you are probably way over pressure according to published load data.
I'm sure your rifle may shoot it fine and you may not have the traditional tell tale signs (heavy bolt, flat primers)these are not always present when over pressure.
I've always said velocity is the best indicator of pressure.

Originally Posted by dannyb

Fully aware I need a lot more data, today was only about checking velocity and ruling out anything that was horrendous (ie a 3" group will never be a viable load for what I want, and will never be better than a 3" group no matter how many rounds you put into it)

You just may as well not invest any energy looking at SD for less than 10 shots - a combination with a true SD of 5fps could by chance give you a 2-shot SD of 25 or 30 if you happened to pick up 2 shots at either end of the range. It's just too meaningless- you can't even use it as a filter for exceptionally bad results.

Originally Posted by gimp

You just may as well not invest any energy looking at SD for less than 10 shots - a combination with a true SD of 5fps could by chance give you a 2-shot SD of 25 or 30 if you happened to pick up 2 shots at either end of the range. It's just too meaningless- you can't even use it as a filter for exceptionally bad results.

Quite right, but as per my previous statement a 3" or for that matter 5" grouping will never be anything better than a 3" or 5" grouping no matter how much data I shoot at it, thankfully I didn't see that. The SD over 2 or even 3 shots is meaningless I am fully aware of that. The charge weight loads were merely to check where I was at with velocity as there is very little published load data for the Ackley.
I needed to see if I could obtain the velocity with the powder and projectiles I chose, before committing to loading more.

I'll be back at the range today with the Nosler charge weight ladder and if I see any promise with the nbt I'll load enough to get some meaningful data.
However if they shoot rubbish then I can exclude them and go back to my eldm load for which I already have pages of data on in my load book.