I would like some reload specifications on 458 ackley improved
458 reload specs please
- Thread starter Peter hunt
- Start date
With most AI's they are wildcats and there is no published data. With a wildcat you just have to take the parent cartridge data and take a SWAG. Scientific Wild A** Guess. Just start going up in .3 grs at a time until you get 100 to 200 fps more velocity than the parent load and you are about done with most AIs. Be careful faces and fingers don't grow back.
Kurz
Silver $$ Contributor
Kurz
Silver $$ Contributor
The Ackley is the oldest version and the Lott is the newest version, with the only difference being the slight shoulder of the Ackley and the straight taper of the Lott:
I worked on these quite a number of years ago, mostly the LOTT since it was easier at the time to get dies and I had the reamer. I thought it would be cool to shoot some of big, heavy 500 grain bullets since those were available in the shop for the asking. Nope, bad move! Way too much recoil to consider using here in the States. I found a box of either Hornady or Speer SPFN in the 350 grain weight which also used a cannelure for crimping. Perfect! Lots of thump and more than reasonably accurate.
I was not shy about running near the top end of the pressure curve then or now so I ran these about 2,800 fps. over IMR-3031 per my notes. The Lott and the Ackley are similar so just start low and work your way up slowly watching for signs of pressure.
Enjoy the experience!
I worked on these quite a number of years ago, mostly the LOTT since it was easier at the time to get dies and I had the reamer. I thought it would be cool to shoot some of big, heavy 500 grain bullets since those were available in the shop for the asking. Nope, bad move! Way too much recoil to consider using here in the States. I found a box of either Hornady or Speer SPFN in the 350 grain weight which also used a cannelure for crimping. Perfect! Lots of thump and more than reasonably accurate.
I was not shy about running near the top end of the pressure curve then or now so I ran these about 2,800 fps. over IMR-3031 per my notes. The Lott and the Ackley are similar so just start low and work your way up slowly watching for signs of pressure.
Enjoy the experience!
Thank you I found this very helpful
What is 458 ai mother case
Because I have been told it is WIN MAG and I have also been told he's a lott
So is it made from a Lott or a win mag ?
According to PO Ackley, on page 502 of his reloading book Vol 1, you neck up a 375 H&H or neck down Norma cylindrical brass.
I'm finding "conflicting" information about the "458 AI" - which seems more likely to be the "450 AI" or "450 Ackley Magnum" and then there also seems to be conflicting information regarding case capacity for the "450 Ackley Magnum".
All of the 458's mentioned so far (458 Win Mag, 458 Lott, 450 Ackley Magnum , 458 Express etc.) use the 375 H&H as the true parent case - with the case length retained from the parent case being slightly longer in each case (Win Mag is the shortest).
If you are referring to the 450 Ackley Magnum, then, the adopted/modified case is the 458 Lott, but it is slightly longer than the Lott. Some sources give the case capacity as a little more (1gr), and others as 1 gr less.
You can safely chamber and fire a Lott in a 450 AM rifle, but not the other way around.
458 Lott loads (starting at the low end and working up) should be safe for the 450 AM.
Kurz
Silver $$ Contributor
Simple.
Call it whatever you wish but the Ackley version of the full length .375 H&H case blown out to accept the 0.458" diameter bullets is still nothing but a WILDCAT. There are no fixed in stone SAAMI or CIP specification with which to judge case capacity or cartridge length. Being a wildcat left the potential for personal design decisions for the reamer dimensions. So quibble over the use of the '0' or the '8' but realize the reasoning behind the variations. There are no standards.
However, Ruger and Hornady agreed to bring the Lott into commercial production with Hornady leading the way to the SAAMI approval. The rest is history and documented.
To my knowledge mostly the Lott case. But I believe some have even taken the standard 458 Win case and used a Ackley version on it. Best would be to go with the Lott case.
I may be wrong, but I believe the original 458 Win that Win came out with was the 375 H&H case necked up to .458, with just a ever so slight taper.
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Kurz
Silver $$ Contributor
As written, the Lott case came after the Ackley version of the 450 or 458 depending on who describes this wildcat. The parent case of the Ackley is the .375 H&H.
From Handloader Magazine, feature By: Terry Wieland | August, 2017
The .450 Ackley Magnum (not Improved) was developed by Parker Ackley in the 1950s, during the heyday of converting Enfield P-17s to cartridges for elephant and Cape buffalo. The Ackley was not alone. There was also the .450 Watts that enjoyed brief fame, because Jack O’Connor took one on an early safari, and a couple of others. The Ackley gained exposure, however, through P.O. Ackley’s 1960 Handbook for Shooters & Reloaders, and it came to stay. Like most of its brethren, it was based on the .375 H&H case necked up and blown out (AI), so it would also fit in the Winchester Model 70.
The introduction of the .458 Winchester in 1956 cut the ground out from under most of the wildcat .450s, but problems with the factory cartridge soon manifested themselves. This ultimately resulted in Jack Lott developing his own .458 in 1971 – merely the .458 Winchester lengthened by .3 inch, which solved the problems. Most of the serious hunters who owned an Ackley, Watts or other wildcat .450, already having loading dies, and with brass easy to make, stuck with what they had. Jack Carter was among them.
https://www.handloadermagazine.com/p-o-ackley-s-big-450
From Handloader Magazine, feature By: Terry Wieland | August, 2017
The .450 Ackley Magnum (not Improved) was developed by Parker Ackley in the 1950s, during the heyday of converting Enfield P-17s to cartridges for elephant and Cape buffalo. The Ackley was not alone. There was also the .450 Watts that enjoyed brief fame, because Jack O’Connor took one on an early safari, and a couple of others. The Ackley gained exposure, however, through P.O. Ackley’s 1960 Handbook for Shooters & Reloaders, and it came to stay. Like most of its brethren, it was based on the .375 H&H case necked up and blown out (AI), so it would also fit in the Winchester Model 70.
The introduction of the .458 Winchester in 1956 cut the ground out from under most of the wildcat .450s, but problems with the factory cartridge soon manifested themselves. This ultimately resulted in Jack Lott developing his own .458 in 1971 – merely the .458 Winchester lengthened by .3 inch, which solved the problems. Most of the serious hunters who owned an Ackley, Watts or other wildcat .450, already having loading dies, and with brass easy to make, stuck with what they had. Jack Carter was among them.
https://www.handloadermagazine.com/p-o-ackley-s-big-450
This is interesting - was always under the impression the AI came "after"... Thank you for the link to the article!
Your previous post mentioned you obtaining 2800fps on IMR 3031 - just want to make dead sure - that was for the 350gr and NOT the 500gr (obviously?)
I picked up 3 boxes of old Hornady 300gr hollow points for a steal, and have been pondering lately if they may be too light for the Lott. Thought they would make cheap "fun" loads, or even decent hunting rounds for small/medium game?
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Kurz
Silver $$ Contributor
Yes, absolutely, it was the two different 350 grain SPFN bullets.
I would hesitate to even consider a 500 grain bullet at 2,800 fps.
That might sting a little...
I did get some 600 grain Barnes moving nicely in a .510 Wells Express (or .500 A-Square) at around 2,450 fps which was a little thumpy. My practice load was an unusual so called 'black powder' bullet which weighed 425 grains. Fired from an 11 lb. rifle it was actually fun to shoot!
Anyway the whole line of .450s or .458s was fun to play with. I might need to take a look at a Lott for the future.
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