Federal loads there 500 grain bullet to 2150 in this caliber and according to my saami specs chart the 470 nitro has a saami spec of 35,000 I have this figure on two seperate saami spec charts.I sent Federal an e-mail asking if there 470 load was equal to or under the 35,000. They sent me an e-mail back stating that the saami specs for the 470 nitro express was 41,000 and that there load was usually around 38,000. So what is the saami spec for the 470 35,000 or 41,000 . and if its 41000 can someone please post the chart that states so hear. Thanks Tanoose

Here's some load data from Speer that "doesn't exceeed Federal's pressure" for whatever that's worth! (and a free bump!!}

http://www.speer-bullets.com/pdf/ReloadingSupplementalDATA/470nitro.pdf

35,000 what? 41,000 what?

Possible psi/cup issue?

JPK

JPK you hit it right i was asking about 35,000 CUP there answer back to me was 41,000 PSI , would this then be the same?

quote:

Originally posted by Tanoose:
JPK you hit it right i was asking about 35,000 CUP there answer back to me was 41,000 PSI , would this then be the same?

Sounds right to me. The old CUP-PSI bugaboo.
The graph of CUP versus PSI is a curvilinear thing with a different shaped curve for each cartridge.

A correction factor to convert CUP to PSI is only an approximation of that curve with a straight line between two points on that curve. Helpful for a specified interval of the curve, but not exact.

I would say that for the .470 NE 35,000 CUP = 41,000 PSI or really close,

Here is what Searcy uses: 2150 FPS IMR 4831 106 grains. He used to use 108 grains of IMR 4831 which gives 2250 FPS. That is with 500 grain bullet.