Advantages to going to an "Ackley"??

Crashman

Crashman

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Hey guys, I have a rifle that i am thinking of improving to the Ackley version. What are the main advantages of reaming the chamber to this version? The rifle is a Remington 700 in 243 winchester, and it already shoots like a dream, I just like to tinker. And what about reaming a 22 Hornet to K Hornet?

Does all of this work improve accuracy or make for flatter trajectories? Or is it just an additional cost to say..."I have an Ackley."??

Also, who would be able to this work, and what would the expected costs of such work be??????
 
I have done a K hornet and its great, not only does it give you more Umph but it's easier on the brass as you now have a shoulder for the case to expand against. As far as your 243 I'd check out the balliastics and see if you gain anything. I think the Ackley Improvements worked really well on a straight walled cases like the Hornet or a 30-30. Some of the Smiths online here could give you better info I'm sure.

I had the 22 Hornet and the 30-30 chambers done for $150.00 each. It was definately worth it both in terms of accuracy and extra distance. The 30-30 AI is just about equal to a 30-06 in the ballistics department and the gophers get an extra few feet in lift from the K Hornet :)
 
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Once in a while, Ackeys have feed issues. Remingtons tend to work well.

My 700/.223AI worked great, but have heard of other 700s that had feed problems in this caliber.


SC..........................
 
I own and shoot a number of Ackleys (and other wildcats), they're fun to tinker with. As mentioned, some of them are more worthwhile then others. The 243 belongs to the 308 family of cartridges, and they are a pretty modern design to begin with. You will see an improvement in velocity, but not a large one. In other cases, the 30-30 or 250 Savage for example, you gain quite a bit more case capacity, and the improvement is very worthwhile. A 250 AI will tread on the heels of a 25-06. There is also less brass stretching; accrued to the improved chamber, but the only cartridge I really noticed this in was the 22 Hornet and Hornet AI. I think they are worth using, and fun to play with. Someone will no doubt weigh in with the "but what if you forget your ammo" argument, but with the AI's, as long as you have the parent cartridge (regular 243 in a 243 AI for example), you're good to go. FWIW - dan
 
In 338.06,it should be a good one,not for velocity gain ,rather flexiblity in powder choices,that little capacity gain would allow the use the 4350s with 225s.
 
downwindtracker2 said:
In 338.06,it should be a good one,not for velocity gain ,rather flexiblity in powder choices,that little capacity gain would allow the use the 4350s with 225s.
Click to expand...

i'm getting 62.0 of IMR4350 with a 225 hornady or nosler seated to the cannelure. Just use a drop tube.

with a few exceptions like the 250 savage, the 30-30, or Hornet, you are paying a few hunderd bucks for about 100-150 fps, and the resale ofthe rifle will drop significantly. As posted above, the 243 is already a modern, straight walled case, and changing the shoulder angle slightly will not get you much.
 
Some AI improvements are definiately an improvement of merit, some are not.
As others have mentioned 223, 3030, 257 Roberts, 280 all shown significant improvement in velocity. I have a 223 , 257 and 30-06 personally. The 223 and 257 are 1s I would repeat again in a heartbeat, the 06 I am pulling the barrel and chalking it up to education.
The 22 hornet and K hornet also are an example of a winning improvement.
I am not sure how much gain there would be in the 243, possibly a marginal velocity increase, but as the 243 is already having a larger than used case capacity I think the gains would be over shadowed by the hassle and loss of barrel life due to fireforming your brass.
As Dan mentioned with several of the AI improved chambers they for some reason will shoot non formed brass just as accuarately as the formed brass, although in a different POI
 
There are certain of the AI cartridges which can show a notable improvement in performance. Generally speaking, if the parent case features considerable taper and a very shallow shoulder angle (30/30, 250, 257,7x57 etc.), the improvement might be worthwhile. With other, more modern designs (308, 243, 223 etc.) any improvement might be difficult to demonstrate.
As a rule, I figure that if the parent case has sufficient capacity to utilize as much of a given powder as possible, there is little to be gained by increasing capacity. This is so unless you are able to increase capacity enough that you can perhaps go to a slower powder.
The 30/06AI is kind of a case in point. The 30/06 will yield about 2800fps with a 180 grain bullet with a top load of 4350. This load will be approaching 100% loading density. The capacity increase of theAI version (about5%) is not enough increase to allow the load to be increased enough to gain much in the way of velocity. The AI version may well be able to show an increase with the slightly slower 4831.
So, if this is so, why do the magnum cartridges enable higher velocities even when using the same 4350 powder? Simply because, in this instance, the capacity is substantially greater requiring that more powder, even if of the same burning rate, be used to get up to the same working pressure. Since there is more powder being used, there is more gas produced and the pressure is maintained for a greater length of time. The capacity difference with the AI cartridge is not great enough to have enough effect.
An interesting aspect of the 30/06AI, and one which I have pointed out before, is that Ackley made a mistake in his original drawings. Consequently, all 30/06AI reamers have been ground incorrectly from the start. When the chamber is cut to the correct headspace, the overall chamber length is too long by about .030". In other words, the neck on the reamer is too long. I discussed this with one reamer maker two or three years ago and he thought he might change his drawings and shorten the neck on subsequent reamers but wasn't sure since he was positive other makers would not be inclined to do so.
In the end, I might be tempted to build myself some of the AI's but would pass on most of them. The extra cost of dies outweighs any slight ballistic advantage IMO. Regards, Bill
 
Okay, so going to a 243 AI is out, it just doesn't seem to make sense given that the rifle already shoots extremely well. But I am still interested in the 22K Hornet, my rifle is a Ruger 77/22 Hornet so I understand that there will be some magazine issues as well. Who can do this work, cut the new chamber and modifying the mag, and what are they going to charge me??

Thanks for all the help guys!
 
Of 100 rifles, my one 257 Roberts Ackley is my best, but I think it only adds 30 fps over the regular Roberts.

The case forming is a big pain, if like me you forget to chamber .004" short.

I am not buying any more Ackley type reamers, but I am getting into 6mm PPC, which has more pain in the a$$ case forming.
 
Mike, I believe Dave Henry in Bently has that reamer. I have dies, but I use them so, no luck there. The Edmonton Gun SHow is coming up in Dec, early, 3rd and 4th or something like that, there's a couple guys with boxes and boxes of dies that usually show up, and they'll probably have some. - dan
 
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