Handi 280 Remington to 280 AI ?

[Fred243]

Would the H&R 280 Remington handle the chamber pressure's of the 280 AI ? I was thinking of rechambering the rifle I have. Also does anyone know what the twist rate is on the Handi 280 ? It has a 26 inch barrel. I don't own any reloading manuals and Hodgdon's website is the only one where i found numbers on chamber pressure's. All of their max loads are under 63,000 psi. Thanks to all

[quickdtoo]

You can't do an Ackley on a fixed barrel, not without setting the barrel back first and refitting it to a frame, you won't be able to use factory ammo in it, I've had a 280 Improved Handi for many years, since the barrel isn't set back, you end up with a bit more case capacity than a true Ackley that's capable of fireforming factory ammo. Twist rates are listed in the FAQs sticky, 280 is 1:10".

Tim

http://www.gboreloaded.com/forums/index.php?topic=187064.msg1098926318#msg1098926318

[Fred243]

Sir, are you saying that if the barrel is NOT set back then the case will be a hair longer than the standard 280 AI ? Or that you simply CANNOT rechamber at all unless you have it refit ? If it's not set back and you use factory ammo, once the cases have been fire formed to fit the chamber are there any safety issue's ? Thank you sir !

[Ol BW]

I think that is what he is saying, that if you ream your chamber for 280 AI then your chamber will be longer than normal, PREVENTING you from firing factory ammo to fireform cases, UNLESS you cut the barrel off the underlug and set the barrel back on the underlug, reweld it and cut off the excess.

[Fred243]

OK, would I be able to use factory ammo such as Nosler Custom without having the barrel set back or you can't do either ?

[Ol BW]

That would be a question for Quick.  It would depend on how deep the chamber is.  I think it would fire them as long as the shell fit flush with the rear of the chamber so the firing pin can strike the primer. . .but I dont know about the safety factor. . .

[dave29]

OK, would I be able to use factory ammo such as Nosler Custom without having the barrel set back or you can't do either ?

You would not be able to use factory ammo to form the AI brass. You would have to get some brass and load the bullets out long into the rifling to hold the case back tight against the breech. Once you do that and fire them,  you will have the correct size brass for your chamber and then you can load your bullets short of the lands if you wish. But no factory ammo will work because it's not a true AI chamber, it's a bit longer.

[Fred243]

Well, poop !! How serious of an issue is it where setting the barrel back is concerned, can they even do that with a single shot ? Almost sounds like I may well need to leave it alone and as is. I appreciate the help guys, Thank you !

[Ol BW]

We didn't say it was impossible, just difficult!
 
Read Quick's post closely.  He has one that has not been set back.  From what I have read it only means that you would have to handload to be able to shoot a gun like that to be able to fit the complete custom chamber.  As he said, it makes the case capacity larger than an AI so therefore the chamber is larger, in this case, longer.  And as Dave29 said, you could start with AI brass and load some bullets long and fireform to get the custom brass.

[dave29]

He should be able to start with regular 280 brass, and seat the bullet out to jamb the rifling using a starting load of powder. That bullet jambed will keep the case tight against the breech and will form his brass.

[quickdtoo]

As I mentioned, you can set the barrel barrel and refit it and create a true Ackley from the parent cartridge, this is done by removing material from the chamber face which in effect sets the barrel back once it's been fitted again, either to another frame or by shimming and fitting to the original frame. I've done exactly than with a fluted bull barrel 270 Win Ultra with a poorly fitted barrel, even did the rechamber by hand, worked perfect, shoots factory 270 ammo just fine. Nosler factory 280 Ackley brass(or ammo) will be too short to fire in the improved chamber, that's the brass I use, it still needs to be fireformed first, it's noticeably shorter than brass fired in my improved chamber, I use a false shoulder to fireform, works much better than loading into the lands, see handloading for an improved chamber in the FAQs.

Tim

[Fred243]

OK, y'all please don't think I'm a dummy ! I've never ventured into this kind of territory before and have done only minor gunsmithing work to a gun. I would of course have a real gunsmith do the reaming for the rechamber. I thought the 280 and 280 AI were the exact same length and just mainly the shoulder change and body taper were the differences. I guess the part I don't understand is how will there be a greater head space if only the chamber has been reshaped ? Doesn't the case still only go in to the rim and wouldn't the outer parts still be the same. Not having a firing pin since it isn't a bolt gun would it not still sit in the same position where the outside of the chamber is concerned ? Thank you again to all for your help !

[quickdtoo]

Depending on the existing chamber, if a smith was real careful doing the reaming and turned the reamer by hand while still in the lathe for the last few thousands of cutting, he may be able to get close without removing the existing neck/shoulder point in the chamber, but that's just a guess, my smith wouldn't even try it.

Tim

[Fred243]

So I'm trying to read as much info as I can and I just read that there's a standard 280 AI and then there's the newer Nosler/SAAMI speced chamber, is this correct ? And is this the issue of not being able to maybe fire form or even use Nosler ammo depending on which chamber specs exist. Why did they do that and what has it accomplished ? Seems to me that someone wanted to hold on to the market for a certain chambering ! The confusion I would think could lead to a dangerous situation possibly. Thank GOD you guys and these forums exist, someone could mess something up really bad without the help. Are there 2 different reamers or are the new reamers being made to the Nosler/SAAMI specs now ?

[Fred243]

Initially I wanted to rechamber my 243 Win to 6 mm Remington but decided that might not work because the 243 is fatter at the top of case body. Am I correct in that thinking or would it be a much easier project to do than the 280 conversion ?

[quickdtoo]

The 6mm Rem won't work, but the Ackley version will, I have two of em, both done by a gunsmith.

Tim