Why Ackley Improved?? Vs std choices

nksmfamjp

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I love the look of Ackley shoulders with bullets sticking way out…..but I also like reasonably priced die sets!

So, that makes me think I should be looking at a 270 Win, 6 Creedmoor, 6.5 Creedmoor, 25-06AI, or ……for a next 473 bolt face barrel chambering. I'd like to go way below 300, run fast twist barrel and high bc bullets.

I'm thinking 6 or 25 cal honestly.

So, what can I get does for?

What real benefit am I getting choosing AI or Sherman calibers?
 
The Sherman designs normally get more capacity in a given length and also maintain plenty neck length, vs Ackley Imp. Generally speaking.

I prefer Sherman to get brass, dies and reamer from one place, for most of the offerings. Headstamp being correct is nice also, when available.
I'm running at 25 Sherman Long Action and awaiting a 25 SS build, now. Same capacity, just short/fat vs long/skinny. Nice having choices.
 
I have shot a 260ai for years and love it. I gain about 200fps over the identical straight 260 barrel (barrels have been 26"). Dies aren't crazy expensive considering they last a long time and the gains I picked up shooting the 140 hybrids out of both.

Edit: I would prefer the 260ai on a medium action but that wasn't available almost 20 years ago when my original 260 was built.
 
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131 SMK from a 22" (no pressure) shot 65 from the barrel (50 FF rounds + 15 MBK rounds)
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RCBS and Redding die sets are readily available for most AI chamberings. I don't recall ever having to special order any of mine. Aside from more speed, you will get longer case life and reduce the need for trimming. I have 22-250AI and 250AI cases with over 20 firings on them and I think I may have had to trim them three times. Back to speed, some AI chamberings I've owned have shown significant increases while others didn't exactly set the world on fire. Cannot speak to the Sherman's but hope too someday soon. The 25SST has been calling my name.

Do your research and have fun. That is what this is all about. Sure, your buddies will laugh at you and guys at the range will give you strange looks when you are powder forming with cream of wheat, but it has all been worth it.
 
Good dies are expensive, so getting anything Ackley might be a 30% premium at best, 100% premium at worst.
If you compare the case volume of a standard cartridge, vs the Ackley version, that is the approximate boost in velocity too.
IMO, the best feature of going with an Ackley'd cartridge is the minimization of trimming.
An additional feature is the reduction of rearward thrust on the bolt face. That thrust translates into felt recoil before the bullet leaves the barrel. While miniscule, it can affect accuracy.
 
What real benefit am I getting choosing AI or Sherman calibers?
I choose AI cartridges for 2 reasons, amongst other Improved designs, these being reducing case taper that causes excessive brass growth reducing unnecessary neck trimming and improving headspace control.
Going from 375H&H to AI or Weatherby is a no brainer, it instantly improves case stretch to almost zero, provides better headspace from the shoulder and cases last a long time, with the H&H, cases last maybe 3 firings before cases crack from over stretching.
The velocity improvement is not my goal, some, like the 375 Weatherby gains of 200fps is a bonus, but most only get 75-150fps gains.

Cheers.
 
I really like Ackley for several reasons.
1. If chambered properly and the need to shoot the parent cartridge comes up, it will typically be very accurate. I shoot when fireforming and love the trigger time.
2. If someone bought or inherited your rifle and was not a reloader they could still shoot your Ackley and never miss a beat. They don't care about the brass.
3. Increased performance with larger capacity.
4. Minimal case trimming and when you add annealing cases last a long time.
I personally don't care about the headstamp. If it says 243 and I can easily tell if its a standard or Ackley case. I run 5 different Ackley's. Maybe I'm biased.

Not sure on the Sherman's. I'm sure its a great cartridge but I've never run them.
 
I went with a 25-06ai fast twist to shoot heavy for caliber higher BC bullets. Im getting 3111fps from a 127gnHHT bullet.
I am a huge 25 cal fan, have 257AI, 25-06, 2 257Bees (1 is new 9" twist custom on Win Model 70 EW) other is factory Mark V Accumark and looking at 8" twist 25-06 unsure if I go AI at this point.
My Dad's renewed interest in hunting @ 79 years has me inspired again.

Cheers.
 
and looking at 8" twist 25-06 unsure if I go AI at this point.
I went with a 7 twist, go with a 7 and AI the chamber and you wont be limited in high BC bullets in the 25. Look up some ballistics estimates downrange with around 130gn bullets at least 3000/3100fps. the ol 25-06 will pack a serious punch.
 
I love the look of Ackley shoulders with bullets sticking way out…..but I also like reasonably priced die sets!

So, that makes me think I should be looking at a 270 Win, 6 Creedmoor, 6.5 Creedmoor, 25-06AI, or ……for a next 473 bolt face barrel chambering. I'd like to go way below 300, run fast twist barrel and high bc bullets.

I'm thinking 6 or 25 cal honestly.

So, what can I get does for?

What real benefit am I getting choosing AI or Sherman calibers?
It boils down to personal preference, intended purpose, improvement goal, or how much time and money you are willing and able to spend. In the .473 bolt face, I have a .270 AI (175 Matrix at 2996 FPS) and .30 Gibbs (180 Berger VLD at 2806 FPS with room to spare), and I am happy with them. Both dies are reasonably priced from Redding.

Here's an example of an improvement goal/opportunity.
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If you are going custom, another option is to go wildcat, design/spec your own sizing and chamber reamer, and have your GS build your dies, including the hydraulic forming die. If you are looking for maximum powder case capacity in .473, the 6.5 WBY RPM is hard to beat. They are pricey, though. I was going to explore this a few years ago but I can only secure a box of 20 brass at the time. Good luck!
 
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