Author Topic: re-chamber to a 270AI  (Read 606 times)

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Offline LONGTOM

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re-chamber to a 270AI
« on: April 05, 2008, 09:31:40 AM »
Can a HANDI 270 be re-chambered to a 270AI as far as pressure goes? Would it be able to come close to a 270WSM with 130s taking into consideration the difference in barrel lenght?

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Offline trotterlg

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Re: re-chamber to a 270AI
« Reply #1 on: April 05, 2008, 09:45:57 AM »
The pressure would probably be OK, however you cannot set back the barrel so you cannot make a 270AI chamber in a Handi.  Larry
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Offline LONGTOM

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Re: re-chamber to a 270AI
« Reply #2 on: April 05, 2008, 09:56:25 AM »
I did not realize that you had to set the barrel back. How about useing a 6.8 and re-chambering it?
Never mind. I went to the H&R web site and see that they don't do a 6.8. SO MUCH FOR THAT IDEA!!!

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"THE TREE OF LIBERTY FROM TIME TO TIME MUST BE REFRESHED WITH THE BLOOD OF PATRIOTS AND TYRANTS".
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That my two young sons may never have to know the horrors of war. 

I will stand for your rights as my forefathers did before me!
My thanks to those who have, are and will stand for mine!
To those in the military, I salute you!

LONGTOM 9-25-07

Offline yooper77

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Re: re-chamber to a 270AI
« Reply #3 on: April 05, 2008, 10:49:23 AM »
Ackley Improved chambers needs a certain amount of case crush when the action is closed, that’s why bolt action barrels need to be set back in order to meet this requirement.  Pressures remain the same; the only real advantage is longer case life.  Changing to an Ackley Improved chamber doesn't make it a magnum and shouldn't be considered such.

In the NEF Handi Rifle the best way to get an Ackley Improved cartridge is to start with a shorter case of desired caliber and rifling twist rate then re-chamber it to a longer Ackley Improved cartridge.

243 Winchester, re-chamber to 6mm Remington Ackley Improved
7mm-08 Remington or 7mm (7x57) Mauser, re-chambered to 280 Remington Ackley Improved
308 Winchester, re-chamber to 30-06 Springfield Ackley Improved

In a 270 Winchester you could have it re-chambered to the 270 Gibbs.
Also, a 30-06 Springfield could be re-chambering to the 30 Gibbs.
Gibbs is a shoulder blown forward to increase case capacity which also changes head spacing.

Yooper77

Offline quickdtoo

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Re: re-chamber to a 270AI
« Reply #4 on: April 05, 2008, 11:35:34 AM »
You can make it a 270 Improved, but you can't make it an Ackley, the difference being a true Ackley chamber can use factory ammo as well as the Ackley version. I've done a 280 Improved Ultra, best accuracy with it has been at ~3200fps with the 140gr TSX, you can read about it in the FAQs and Help sticky in the Handloading section, Handloading for an Improved Chambered Handi. ;)

Tim
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Offline LONGTOM

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Re: re-chamber to a 270AI
« Reply #5 on: April 05, 2008, 06:33:28 PM »
I understand about the AI setback and all now. I also read the FAQs on the 280I you did. So now I am back to wondering again. How much velocity increase do you guess I would get with a 270 I I over a factory 270? Would it be enough to justify the trouble and expense of it all?

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"THE TREE OF LIBERTY FROM TIME TO TIME MUST BE REFRESHED WITH THE BLOOD OF PATRIOTS AND TYRANTS".
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That my two young sons may never have to know the horrors of war. 

I will stand for your rights as my forefathers did before me!
My thanks to those who have, are and will stand for mine!
To those in the military, I salute you!

LONGTOM 9-25-07

Offline quickdtoo

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Re: re-chamber to a 270AI
« Reply #6 on: April 05, 2008, 06:40:30 PM »
You're at a deficit with the 22" barrel of the 270, the 280 Ultra has a 26" barrel, so I think there's merit in taking advantage of the longer barrel, but 50-100fps is probably a reasonable maximum to expect and still stay in Handi friendly pressures.

Tim
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Offline LONGTOM

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Re: re-chamber to a 270AI
« Reply #7 on: April 05, 2008, 06:48:42 PM »
That's what I was afraid of. Not enough to bother with.
Like I said before "SO MUCH FOR THAT IDEA".
Thanks Tim   
Keep up the the great job you are doing in keeping us in line with our crazy dreams.

LONGTOM
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"THE TREE OF LIBERTY FROM TIME TO TIME MUST BE REFRESHED WITH THE BLOOD OF PATRIOTS AND TYRANTS".
THOMAS JEFFERSON

That my two young sons may never have to know the horrors of war. 

I will stand for your rights as my forefathers did before me!
My thanks to those who have, are and will stand for mine!
To those in the military, I salute you!

LONGTOM 9-25-07

Offline singleVI

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Re: re-chamber to a 270AI
« Reply #8 on: April 07, 2008, 11:49:40 AM »
So could a .30-30 Handi be rechambered to 30-30 Ackley Improved? Can it be done by hand with the right reamer or is it a machine job?

Offline quickdtoo

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Re: re-chamber to a 270AI
« Reply #9 on: April 07, 2008, 11:56:59 AM »
It's been done by hand and I plan on doing it when I get the reamer myself using my drill press for alignment only, ordered it a while back with the 460 S&W reamer from 4D when Fred gets it in stock. Since the 30-30 headspaces on the rim, it can be a true Ackley, although chamber tolerances may not provide the best case life if care isn't taken to insure case growth is in the right places, in other words, if the shoulder isn't supported, head separations are possible. I'll be using 375 Win brass to handle the extra pressure and get good case life.

Tim
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Offline alan in ga

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Re: re-chamber to a 270AI
« Reply #10 on: April 16, 2008, 10:12:38 PM »
"Since the 30-30 headspaces on the rim, it can be a true Ackley, "

WHEWW~! last time I said/posted that on this sight all heck came loose!
I agree. It is a true Ackley. Just as much as the origional chamber is a 'true' 30/30 Winchester.
Built a few Ackleys here.

Offline Steve P

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Re: re-chamber to a 270AI
« Reply #11 on: April 17, 2008, 04:30:12 AM »
You are correct in making a 30-30 improved and even an Ackley improved, but do not rely on head-spacing on rim if you expect any case life.  You still want to head-space on the shoulder.  Look at the difference in rim thickness in several different brands of ammo.  Also look at the difference in rim rebate in several different barrels.  Always set your dies so it takes a firm closing of your action on a sized brass.  Factory loads should be considered 'fire form' loads.  Set the shoulder back .001-.002 IF at all.

Steve  :)
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