280 AI alert

In general, what is the difference in length from base to datum line on the should between a go and no go gauge for cases in the .30-06 class?
 
Answer from Redding's website:

They currently manufacture reloading dies for the SAAMI 280 Ackley Improved. And that die could also be used to reload for the original, traditional 280 AI... IF the reloader backed this resizer die away from the shell holder ~0.014 inches.

The Redding article states Redding also manufactures reloading dies in limited numbers for the original 280 A.I. cartridge, as a custom ordered and manufactured item. And sell them at their higher custom die prices, no doubt.

A guy could load for both cartridges with either set of Redding dies, IF he was in the know.

The two cartridges are basically clones in every other dimension except the 0.014" shorter headspace on the SAAMI adopted cartridge.

But many never come to that correct understanding.
 
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In general, what is the difference in length from base to datum line on the should between a go and no go gauge for cases in the .30-06 class?
I think it's typically 0.004" between a Go and No Go gauge. The Go being 0.004" shorter than the No Go.

But here's the SAAMI standard for MIN MAX headspace for the Chamber of the 280 Ackley Improved. Acceptable headspace from the breech face to datum on the shoulder spans a distance of 0.010". MAX 2.150" - MIN 2.140" = 0.010".

SAAMI chamber tolerance 280 Ackley Improved.JPG
 
Without lookin', I'm thinking the difference between the gauges for .30-06 is generally .006". .010" is allowable by the print, but .006" is the accepted norm. My gauges for .308 Win. have a difference of .004. Most custom cut chambers are cut closer than that. For a "hunting" chamber, maybe "GO" + .002" max. Saves on brass that way and allows for a proper shoulder 'bump' with your sizing dies. Cut a chamber right at 'GO' and your std die may not 'bump' , in which case a custom sizing die would be needed. For what it's worth, my personal .280 AI (Nosler SAAMI) won't 'crush' Win head stamped .280 Rem cases, and head space is set at "GO" + .002" . I jam the bullet for fire forming. Accuracy is quit acceptable with my fire forming loads,,, good enough for hunting within 500yds, or so.
 
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Answer from Redding's website:

They currently manufacture reloading dies for the SAAMI 280 Ackley. And that die could also be used to reload for the origigal, traditional 280 AI... IF the reloader backed this resizer die away from the shell holder ~0.014 inches.

The Redding article states Redding also manufactures reloading dies in limited numbers for the original 280 A.I. cartridge, as a custom ordered and manufactured item. And sell them at their higher custom die prices, no doubt.

A guy could load for both cartridges with either set of Redding dies, IF he was in the know.

The two cartridges are basically clones in every other dimension except the 0.014" shorter headspace on the SAAMI adopted cartridge.

But many never come to that correct understanding.

I do note that they use the 6.5-06 A square for the 6.5-06 dies which is different from what you'd expect for the 6.5-06.
 
Ackley's 280 AI was and still is a wildcat and should be treated as such. The SAAMI cartridge is not. I headspaced my 280AI rifle with a PTG 280AI gauge and have fired many factory 280 Rem cartridges as well as Nosler brass without issue. If one is expecting to fire factory 280 ammo, I'd suggest setting headspace as ackley intended with a slight crush fit at the shoulder neck junction on whatever factory round you intend to fireform. Seems that this would bring up the question of, is all factory ammo exactly the same dimension at this point? When I made 250 savage ai brass from 22-250 brass, I ran it over a 26 cal mandrel and then into my 250ai sizer that was set to bump my shoulder and had a snug fit in my chamber for forming and had no issues at all.
It doesnt matter what Nosler did or didnt do, it is the SAMMI round now and Ackley's rifles are still wildcat improved cartridges as they always were.
 
Wow, JE's name still shows up and warms my heart.
The whole 280 variants "thing" is quite a subject. It's been covered on quite a few threads here even with the Remington 280 and 7mm express switcheroo. It can give one a migraine trying to sort it all out.
I have a .280ai, i was impressed with the 7mm-08, I learned about the 7x64, the .280 and some suggested the .280ai.

For all the research I put in I did not find any info about conflicting info on the 2 version s .

I bought an Ackley based on it being a fast 7mm hot on the heels of a 7mmRm without the recoil and I bought headstamped Nosler cases and Redding dies. How easy was that? Then I learn all this.

Probably hasn't affected me that much but yeah it's all interesting.
 
Wow, JE's name still shows up and warms my heart.
The whole 280 variants "thing" is quite a subject. It's been covered on quite a few threads here even with the Remington 280 and 7mm express switcheroo. It can give one a migraine trying to sort it all out.
Aye Sir! His legacy lives on amongst us.
 
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