ackley

[huntwithme]

you always here how fast they are but does anyone know how much energy the 243 ack, 6mm ack or the 7/08 ack has at say 500 yards. i'm trying to decide which one is the best to rebarrel. the 243 and the 6mm use 100 gr and the 7/08 us 120 gr. all with 26 inch barrels. or would you just go with say a 6mm/284 or 6mm creedmoor or even a 240 weatherby.

 

[cohunt]

download a free hunting app for your phone and punch some numbers in
or on the computer you can use this link http://appliedballisticsllc.com/ballistics/

 

[codyadams]

you always here how fast they are but does anyone know how much energy the 243 ack, 6mm ack or the 7/08 ack has at say 500 yards. i'm trying to decide which one is the best to rebarrel. the 243 and the 6mm use 100 gr and the 7/08 us 120 gr. all with 26 inch barrels. or would you just go with say a 6mm/284 or 6mm creedmoor or even a 240 weatherby.

Basically, a 6mm ai will have more energy than a .243 ai, and a 7mm-08 ai will have more energy than either of the 6mm cals. This can be scewed, say you use a 120 in the 7mm with a very low bc and a 100 in the 6mm with a very high bc, but the potential for each cartridge's max energy at 500 will go most energy 7mm-08 ai, then 6mm ai, and finally .243 ai.

Whether you rechamber an existing gun or buy a new one depends on many things, how much barrel life is left on the current guns, accuracy, if you want an excuse to get a new gun, components you may already have on hand, etc.

 

[B23]

If you want to sling the heavies or just want whatever bullet you choose to go fast, I'd pick the 6-284.

The 6-284 will easily shoot faster than the 243AI or the 6mm AI and do so without the extra hassle of fireforming. The 6-284 is super easy to load for and making brass is as simple as a one time pass through a 6-284 FL die or bushing die.

The Rem 6mm suffers from having mediocre at best brass and with long, heavy for caliber bullets, it really needs to be used in a long action.

The 243AI is a great cartridge as well, but gains so little when it's improved, for me, it just isn't worth my time to fireform.

If you have your heart set on a 243AI maybe talk to Defensive Edge Rifles about having them build you their 243 Terminator. It's their version of a 243 Improved and you can buy already formed Lapua brass that is ready to go right from Shawn.
https://www.defensiveedge.net/index.php/terminator-cartrdige-data/138-243-terminator

 

[HARPERC]

,,,,,,If you want to sling the heavies or just want whatever bullet you choose to go fast, I'd pick the 6-284.

.......The Rem 6mm suffers from having mediocre at best brass and with long, heavy for caliber bullets, it really needs to be used in a long action.

........The 243AI is a great cartridge as well, but gains so little when it's improved, for me, it just isn't worth my time to fireform.....

Easy as 1-2-3.

I've had the 6mm for a very long time-but if/when we shoot it out I won't go that way again.

 

[codyadams]

Easy as 1-2-3.

I've had the 6mm for a very long time-but if/when we shoot it out I won't go that way again.

Isn't sourcing brass kind of a pita?

 

[HARPERC]

....Isn't sourcing brass kind of a pita?.......

I've got more brass than I'll use. I won't say it's as good as what's available for other cartridges, but good enough kids are still taking game with it, some are kids of kids got their start with it.

Hoping to get it out for coyotes this winter.

 

[Mram10us]

I've sold 243ai reamers and setup and will probably do the same with my 7-08ai stuff because I'm just not into fireforming anymore. So many cartridges you don't need to mess with, that give just as good of performance and accuracy... to each their own, but I'm done with building ai

 

[codyadams]

I've got more brass than I'll use. I won't say it's as good as what's available for other cartridges, but good enough kids are still taking game with it, some are kids of kids got their start with it.

Hoping to get it out for coyotes this winter.

I was considering building a 6mm AI for shooting light bullets over 4000 fps for a super flat 400 yard coyote lazer, but in a few searches online couldn't come across much. I was able to find some, but it was just remington stuff I believe. I may still do it eventually, just for fun.

Sorry to derail the thread.

 

[Alibiiv]

you always here how fast they are but does anyone know how much energy the 243 ack, 6mm ack or the 7/08 ack has at say 500 yards. i'm trying to decide which one is the best to rebarrel. the 243 and the 6mm use 100 gr and the 7/08 us 120 gr. all with 26 inch barrels. or would you just go with say a 6mm/284 or 6mm creedmoor or even a 240 weatherby.

I would like to say that there are a number of variables that go into the formula for determining muzzle energy like bullet weight, velocity and distance "what distances are you trying to calculate muzzle energy". Take a light bullet, get it going at a high muzzle velocity and....at the muzzle the energy will be extremely high, but.....when you get out a distance that muzzle energy will diminish as velocity drops off. Where a heavier bullet will leave the muzzle not quite as fast, but....will hold the muzzle energy at longer distance due to the heavier weight of the bullet. What I am trying to say is that "feet-per-second" is not the only element in the equation for determining muzzle energy. Yes it is simple if one only measures muzzle energy at the muzzle, but....add distance to the equation and it gets complicated. Hope this makes sense to you?

What cohunt wrote in his reply to you about the Applied Balllistics app will give you about all the information that you will need to determine what cartridge does what when determining muzzle energy, muzzle velocity, drop and what to expect from a particular bullet (weight/design/ballistic coefficient) at a particular distance. I use this app with my chronograph, have found it to be quite accurate for my shooting/hunting requirements. I suspect that if you get the app you will answer a number of the questions that you have about Ackleys and other cartridges.

I don't know if you reload or not, if not I would suggest not going to an Ackley Improved "unless" you intend to reload, and even if you did intend to take up reloading, I would not recommend an Ackley Improved because in my opinion it is a lot of information to absorb and apply to make wildcat brass; not to mention expense for dies. I suspect that some may disagree with this position, but fireforming brass to make wildcat brass is time consuming and somewhat expensive. I'd suggest rebarreling for something that you can find ammunition off the shelf and components to reload the cartridge if you want to. From your OP it appears that you are looking to rebarrel a short action is that correct?? Before making a determination of what you would like to rebarrel a rifle for, what do you intend to use the rifle for? With that in mind you could go from there to determine cartridge, barrel length, weight. For overbore cartridges (small caliber bullet/large case/powder capacity) I am a fan of the 26 inch barrel as it gives the powder a better chamber to burn give better performance (muzzle velocity). I just built a .270 Ackley Improved with a 26 inch barrel and I am very happy of the performance of the cartridge.

 

[MagnumManiac]

Most AI cartridges gleen a maximum of 150fps or LESS over the parent, 2 exceptions are the 250 Savage and 22-250.
I have had several of them, once shot out, I just went back to the parent case except in 1 instance, my 22-250AI will always be an AI due to it's extreme accuracy.
3 barrels so far and it shoots consistently more accurately than the parent. More accurate that 2 Swifts I've had, on par with my 222 that puts 20 rounds into a ragged hole, almost Benchrest groups.

The energy increase is far less than you think, animals won't know the difference, but I always lean toward bigger and heavier.

Cheers.

 

[SealT5]

The 6x284 runs like a scalded ape!

 

[CUTTER1]

I've built AI cartridge rifles for years everything from 22-250AI & 223AI to 338AI and for a reloader they are sometimes a challenge that is almost always worth it in performance gain! The 244AI has been a special favorite. Have shot out several as windy days PD rifles. With the new bullet selection in 6mm it's a great choice!

 

[coyotezapper]

Most AI cartridges gleen a maximum of 150fps or LESS over the parent, 2 exceptions are the 250 Savage and 22-250.
I have had several of them, once shot out, I just went back to the parent case except in 1 instance, my 22-250AI will always be an AI due to it's extreme accuracy.
3 barrels so far and it shoots consistently more accurately than the parent. More accurate that 2 Swifts I've had, on par with my 222 that puts 20 rounds into a ragged hole, almost Benchrest groups.

The energy increase is far less than you think, animals won't know the difference, but I always lean toward bigger and heavier.

Cheers.

I agree with this statement. For me I did two ackleys 7-08 and 338-06 for two reasons. The AI 40* shoulder keeps case trimming to a minimum and reduces bolt thrust. The blown out case and shoulder slow down the brass flow when fired resulting in less case length growth. The second reason is a slight gain in accuracy and energy. In the 338-06 not so much but the 7-08 AI runs right on the heels of a 280 but in a short action. The downside is fire forming brass. If the rifle is meant for varmint shooting then this can be done while shooting PD's but for a hunting rifle this can be a long process. I usually do at least a hundred cases and if brass is good quality this hundred will last the life of the rifle. For a varmint rifle I would just pick a number to fire form and then buy that many cases from the same lot to keep everything consistent.