7 rem mag or 280 ack?

[ImBillT]

LOL! I have heard that improving a 280 Rem (60,000 PSI) to .280 AI will increase pressure to 65,000 PSI. That's why I went with improving .270 Win (65,000 PSI) instead; if the same concept/principle applies, a .270 AI should be 70,000 PSI.

Pressure specs are just that. "Specs". If you load up to pressure signs, you're over spec for most cartridges. 65ksi will show pressure signs with a lot of primers and brands of brass, but not all. 60ksi might show signs with Remington or Norma brass and Winchester primers.

The 280AI is a SAAMI specified cartridge. So is the 280 Remington. The specs chosen had reasons behind them, but no, improving the 280Rem didn't raise anything's capability of handling pressure. The shape of the case didn't have anything to do with the specified pressure.

What makes you think that dropping from .284" to .277" would allow you to go to 70ksi?

 

[Rflshootr]

What is ksi?

 

[ImBillT]

What is ksi?

Shorthand for thousand psi. It's fairly common in engineering texts. Or at least it used to be.

 

[Rflshootr]

Oh, I see now. I thought it was a british rapper. And one of those is enough. We don't need 70, or even 65 for that matter.