What I posted in #51 is an extract from Whidden's website Q&A (https://www.whiddengunworks.com/faqs/).
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Question about Ackley Improved
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7stw
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So far, this is a nice thread. Its peaceful, that's the way it was intended. Nice info , even for the vets.
Lonewolf74
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Thank you Feenix and I know it was directly from they're site and that they consider 3 pieces of brass a better option then a reamer print. I just could of swore I seen somewhere on the site stating the best way is for it to be 3X fired brass. It's possible I read it somewhere else though cus I can't seem to find it again. Either way we do know that brass isn't fully formed till about the third firing so it would be the very best way to have a custom die made
The stability of brass after 2-3X firing is not the same as taking an imprint from your rifle's chamber with a full load. Jim and his crew can take critical measurements from the average of the 3 1X fired brass (better than the reamer print) from your rifle to make you a custom die. There's a lot of PSI on a regular load to take the chamber's shape, just saying.
Below is the pre-forming my .30 Gibbs using .35 Whelen brass
From L-R
1. .35 Whelen virgin brass
2. Establishing a false shoulder
3. After the COW method with 11g WSF
4. After running through the re-sizing die.
As you can see, it has taken a high percentage of the chamber's form already.
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nkyshooter
Well-Known Member
actually ... I use the 260 rem dies to reload my 260 AI ... collet to neck size and the seater to seat ... for full length, I use a redding body die then a second pass to resize the neck and decap ...
I'm not saying this works with every brand of dies, but it seems to be consistent on Lee dies for me ...
BTW - my runout averages 0 +/- .0005" (half thou)
nkyshooter
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Hugnot
Well-Known Member
I have had a .257 AI and now a 6mm AI - 40* shoulder.
My gunsmith likes to cut the chamber slightly short so I get a crush fit the junction of neck & shoulder when fireforming - tight fit, essentially no headspace when fireforming. For subsequent loads I use a shortened shell holder to maintain correct head space.
I use whatever pistol primers I have available and whatever pistol powder I have, When fireforming, I start at 10% of the total capacity load then work up so I get nice sharp shoulders.. Coffee grounds (dry) sound good for a filler vs. cream of whatever. Like, if 60 grains of pistol powder fills the case to the top of the neck, I start with 6 grains, the last FF session used 9 grains of HP38.
Dies are available for popular AI calibers. My 6mm Lee collet neck sizer works with 6mm AI brass. I have a Redding 6mm AI F/L sizer die (stock item) and I use a generic 6mm Hornady seating die. Necks are turned to .268 diameter. My brass is adequately fireformed at chamber pressures of about 60K PSI - this is after COW fireforming using full charge loads with bullets. I would not select any AI cartridge that required custom dies - $$ - just me.
With the 6mm AI the case capacity is increased about 10% resulting in 80-100 FPS increase, case stretching is almost nothing, feeding is excellent in my Ruger M77 MKII LA rifle. COAL is right around 3 inches depending on what bullet I use. I planned on getting a 8 twist 6mm AI on a FN commercial Mauser but gave up on the idea when the intended rifle would not feed dummy 6mm AI rounds because the shoulder hung up on the top collar inside the receiver ring - that rifle was re-barreled to 6mm-06.
I use my 10 twist 6mm AI with 87 grain VMax bullets & H4350, RL16,or IMR4831 against rodents - real good performance - 600 yards and beyond. Many 3 shot clover leaf groups and under 2 inches at 300 - good enough for me.
The generic Hornady seater die is used for; .243W, 6mm Rem, 6mm AI & 6mm-06. Brass diameter at the shoulder is of no consequence.
Just remembered - under 10* & snowing - time for a Dickel & fireplace (gas).
My gunsmith likes to cut the chamber slightly short so I get a crush fit the junction of neck & shoulder when fireforming - tight fit, essentially no headspace when fireforming. For subsequent loads I use a shortened shell holder to maintain correct head space.
I use whatever pistol primers I have available and whatever pistol powder I have, When fireforming, I start at 10% of the total capacity load then work up so I get nice sharp shoulders.. Coffee grounds (dry) sound good for a filler vs. cream of whatever. Like, if 60 grains of pistol powder fills the case to the top of the neck, I start with 6 grains, the last FF session used 9 grains of HP38.
Dies are available for popular AI calibers. My 6mm Lee collet neck sizer works with 6mm AI brass. I have a Redding 6mm AI F/L sizer die (stock item) and I use a generic 6mm Hornady seating die. Necks are turned to .268 diameter. My brass is adequately fireformed at chamber pressures of about 60K PSI - this is after COW fireforming using full charge loads with bullets. I would not select any AI cartridge that required custom dies - $$ - just me.
With the 6mm AI the case capacity is increased about 10% resulting in 80-100 FPS increase, case stretching is almost nothing, feeding is excellent in my Ruger M77 MKII LA rifle. COAL is right around 3 inches depending on what bullet I use. I planned on getting a 8 twist 6mm AI on a FN commercial Mauser but gave up on the idea when the intended rifle would not feed dummy 6mm AI rounds because the shoulder hung up on the top collar inside the receiver ring - that rifle was re-barreled to 6mm-06.
I use my 10 twist 6mm AI with 87 grain VMax bullets & H4350, RL16,or IMR4831 against rodents - real good performance - 600 yards and beyond. Many 3 shot clover leaf groups and under 2 inches at 300 - good enough for me.
The generic Hornady seater die is used for; .243W, 6mm Rem, 6mm AI & 6mm-06. Brass diameter at the shoulder is of no consequence.
Just remembered - under 10* & snowing - time for a Dickel & fireplace (gas).
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7stw
Well-Known Member
On my 25.06ai,I could be wrong, but I thought, that I had accidentally tried to seat bullets, in ai fired brass, and seem to remember, that if you push it up as you did with standard 25.06, the die body hits the brass, before it get to the bottom. Either way, the neck isnt being supported because it cant get there. The 25.06ai, nearly becomes a straight tube, and the shoulder, drops into a relatively short neck.
7stw
Well-Known Member
15 grains of unique, COW to the base of neck, stuff with soap, bang. I think I have a little headroom on the charge, as the shoulders have a hint of roundness to them
I use Lapua brass, and it's pretty tough stuff. I like the coffee grain idea. But, I do know that the first full house fully blows out the corners nice and sharp.
You'll never pry mine away from me. She is sweeeeeeet!. And wicked tooooo!
7stw
Well-Known Member
Another thing that's pretty cool, with the 25.06 ai
When you start with 30.06 brass, when you resize neck, to 257. It leaves a little dimple, at the top, that serves as a false shoulder, and eliminating headspace issue when fire forming with no bullet. At least, you are firing at least one less bullet through the bore.
When you start with 30.06 brass, when you resize neck, to 257. It leaves a little dimple, at the top, that serves as a false shoulder, and eliminating headspace issue when fire forming with no bullet. At least, you are firing at least one less bullet through the bore.
Hugnot
Well-Known Member
An interesting read about AI cartridges.
My opinion is that in some cases like .243 W, .260 Rem, & 7mm08 it is not worth the effort. In other cases like .22-.250, 6mm Rem, .280 it is worthy. I once had a 6.5-06 AI and I still have not determined if had any real advantage; I shot 120 Nosler BT's with lots of H4831 at rockchucks and it killed them. If I had a good chronograph then I might have been disappointed.
I rather have a .22 CM than a .22-.250 AI.
My opinion is that in some cases like .243 W, .260 Rem, & 7mm08 it is not worth the effort. In other cases like .22-.250, 6mm Rem, .280 it is worthy. I once had a 6.5-06 AI and I still have not determined if had any real advantage; I shot 120 Nosler BT's with lots of H4831 at rockchucks and it killed them. If I had a good chronograph then I might have been disappointed.
I rather have a .22 CM than a .22-.250 AI.
I have always agreed with this until the last few years with all the new powders available it may be worth it now
Agree with the new powders available. However, my first AI was my 243. I went Ackley to avoid so much case growth and trimming so often. Performance improvement wasn't even a consideration
Here are some Ackley imprved examples and a couple of other misc.
they are as follows
223, 223AI
22-250, 22-250AI
243, 243AI
260, 260AI
22-06 not fully formed
6-06, 6-06AI
25-05, 25-06AI
6mm Mach IV 257 WBY necked down to 6mm 264WinMag brass also works, but can't withstand as much pressure.
Dean
they are as follows
223, 223AI
22-250, 22-250AI
243, 243AI
260, 260AI
22-06 not fully formed
6-06, 6-06AI
25-05, 25-06AI
6mm Mach IV 257 WBY necked down to 6mm 264WinMag brass also works, but can't withstand as much pressure.
Dean
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