Ackley Discussion

RobP

RobP

CGN Regular
Rating - 100%
224   0   0
Location
E. Ont.
Of the PO Ackley "Ackley Improved" cartidges....which ones make the most sense?

I'm thinking of 270 AI...... Always been somewhat intrigued by them and kind of like the idea of being able to fall back on factory ammo if needed....

Rob
 
My understanding is that the .257 Roberts is one of the most efficient, or benefits the most from being "Ackleyfied". Really is it that important to "improve" a cartridge? Probably not for the hunting that most of us do, and if a little more power is "needed" then a larger caliber, or cartridge with more case capacity is deffinately available on the market. For instance in the .270 bore, what about the .270 WSM, or the .270 Weatherby? By no means am I suggesting that you go that route, heck an Ackley cartridge is fun, and different, that's what attracts me to them. Not the norm., I don't hunt with anybody that uses one. For the most part most of my hunting companions wouldn't know what you meant if you said .270 AI, or even .270 Ackley Improved for that matter. I've got a couple of Ackley cartridges, with plans of at least on more, as well as a couple Mashburn chamberings. I bought a 25/06 AI, and a .280 AI from one of the members on here, both super rifles for hunting. Although they claim the 25/06 AI to be less than efficient it's still fun, because none of my friends have one. The .280 AI is basically a 7mm Rem mag with out the belt, at least thats the performance one could expect. I've got a reamer for a 6.5/06 Ackley Improved, that I plan on building a hunting rifle from, another fun toy. My Mashburn chamberings include the .218 Mashburn Bee, and the .350 Mashburn Super magnum. For the 6.5/06 AI, and the .350 Super mag there isn't factory ammo to fire in them, but still fun none the less. If you've got an improved chamber, then you'll deffinately want to reload.
 
From personal experience the 30'06 AI is no screaming hell for out performing a regular 30'06.
Also from surfing around it appears thet the 280AI is a worthwhile venture.
 
250 AI (not the Roberts) is the most efficient of the AI improvements, the 35 Whelen the least. Everything else falls in between. One of the writers for the gun rags has done a lot of research on this, and basically, whatever the percentage of case capacity that you gain, your velocity increase will be one quarter to one half of that number. I still like them, and have had AIs in various calibers over the years, still have a few. - dan
 
I have had quite a few Ackley Imp cartridges over the years, three 223s, two 250-3000s, 7X57, two 280s, two 30-30s, two 30-06s and an 8mm-06.

The best of them all as far as improved velocity over factory is the 250-300, 3200 with 100 gr bullets in a 22" Sako. Next best is a toss-up between the 280 160s at 3000 in a 22" Ruger and the 30-30, 150s at 2700 fps out of a 20" Model 94.

The real sleeper is the 223 Ackley that gives 40 gr bullets almost 4000fps.

They are all improved as far as case life goes.

Ted
 
Have a 280AI and really like it, love comparing it to friends 7 Rem mags over my chronograph. Also like the 223 AI as mentioned by someone above, it works wonders in the gopher patch and still has good barrel life. My 243 AI was a bit disapointing and was sent down the road.
 
Thanks guys - I'm considering the 270 -- have one which I would get the chamber done on. Where can I find a link giving what the additional powder capacity would be?
 
Rob, the add'l powder capacity on my 280 AI was three grains. The load was five grains more than in the standard case. My guess is that the 270 AI would be similar.

Maybe back40sniper can let you know what his is, as well. That will give you apretty good idea.

Ted

Edited to differentiate between case capacity and loading.
 
Last edited:
The chamber is reamed so that there is less body taper, and the shoulder angle is increased. Once a case is fireformed it will hold more powder, so increased velocity is possible. Other advantages are claimed, but this is the most significant. An AI chamber is cut so that a factory cartidge will headspace correctly; factory ammunition can be safely fired in an AI chamber. If an existing barrel is being converted, this means that the barrel must be set back before the chamber is reamed. Often a GO gauge is used as the NO GO for chambering to insure a minimum fit for factory cartridges. My experience is limited to a few .22-.250AI rifles. The AI version essentially gives Swift performance.
 
Ackley was a gunsmith from Utah. He came up with the improved cartridge design bearing his name, although other 'smiths had thier versions as well. Basically minimum body taper, and a 40 degree shoulder, with the chamber cut so that you can fire factory rounds in it for fireforming (usually 0.004" shorter then the regular cartridge, to allow minimal headspacing when firing). There is also a correlation between some Ackley improveds and less brass stretching, the 30-30 and 303 come to mind. - dan
 
less thrust on the bolt as well. I know for sure the 6.5x55 and .303br show great returns on the easy mod. Feeding can be a problem.
 
actually none of them make a whole lot of sense....most don't feed nearly as smoothly as thier standard shaped counter parts and there are other cartriges which will do whatever the AI's do...I had a 7-08AI and rechambered it to 284 Win...it feed better, shot faster and with the same accuracy. Had a 223AI too...fed poorly at best, give me a 22-250 any day. I currently have a 280AI and often wonder why...the standard 280 isn't that far behind in velocity...one can always go to a 7WSM and have 280AI performance in a shorter action and a short fat case...with no fireforming...

but,..if you like Ackleys have at 'em...the 280AI will be my last.
 
There are a number of things to take into consideration. Purchase price, resale demand & value, what is commercially that is close enough to meet your needs to name but a few. ;) However, IF something along the lines of an 'A I' caliber is your 'burning desire', go for it by all means. Something to that may help you make your choice is an indepth look at P.O. ACKLEY's two volume HANDBOOK FOR SHOOTERS & PELOADERS:cool:
 
Hmmmmmm..Rembo. I was sittin here mindin my own buisness untill that comment.

I have 1 22.250 A.I. on a Sako with a Lilja bbl and a Canjar. 220 velocities and little if any case stretch. Sorry but can't say that 'bout my Swift. I need to trim almost every firing. No feed problems.

257 A.I One on a Winchester featherrweight and one on a Mauser with a hvy bbl. Winchester has taken many w/t's 120 speer at same vel as 100 in a 257 rob. No feed problems with either rifle.

6.5 x 57 A.I. Custom Mauser. Referred to as the 260 A.A.R. also (Apex allround rifle) Must be a reason for that but I really havn't shot this one much so I won't sing it's praises, oh except, no feed problems.

7 x 57 A.I. Custom Mauser. This is probably the love of my life. 7 rem velocities with low recoil, little brass stretch, less powder, and oh yes, no feed problems.

280 A.I. Remington Mountain Rifle. Still working up load for this one, but according to a nbr of ppl., one of the best of the AI's. We'll see. No feed problems.

30.06 A.I. Of the two that I have owned (one pre 64 win out of the Winchester custom shop and one Whitworth) I found that velocities approaching 3000 f.p.s. with 180's were possible. 2992 average with the Whitworth. And this is the A.I. that is supposed to be the least efficient of the bunch. I sold the Whitworth to own the Custom Winchester. That was an unfortunate mistake. The Winchester had a Pendleton brake that gave me a headache in 3 shots and did not shoot to my expectations. No feed problems.

I guess I like the A.I. carts., but they are not for everyone. They are one of the easiest wildcats (if you consider an improved cartridge an actual wildcat) to use. ie. fireforming parent ammo to produce cases, little trimming, efficient powder use......and last but not least .....###y.

I have seen feed problems in A.I. chambred rifles, but it is not restricted to these. For example anyone heard of feed problems with the W.S.M.'s?? With any Mauser style action cartridges have to be loaded to the rear of the magazine, but I think that's a gimme.

Anyway Rick, if you decide to sell your 280 A.I., I'm sure you will find lots of people interested in it, as they know the quality of your work.
 
Improved cartridges are great and DO have a lot of benefits. In my experience, the benefits are usually overstated. As noted before, the velocity increase is normally 1/4 to 1/2 of the % increase in capacity. Some folks claim a lot more, but are really just running higher pressures. Case growth is moderated somewhat, but the importance of that benefit is also overstated unless you're loading really hot and full-length sizing.

Benefits are greater with highly tapered shallow shoulder cases. One of the more dramatic improvements is the 300wby from the 300H&H. Not an 'Ackley' improvement, but same principle.
 
You must log in or register to reply here.
Back
Top Bottom