SAMMI
 

Does SAMMI have a rating for the 300 Whisper?
I want to build a small ring mauser and would really like to know the CUP pressure rating.

Any Guesses?

My guess is that there is no SAMMI standard as this is a proprietary cartridge... If I come accross a pressure I will add it here later!

The pressure will be no more than a .221 FB or a .223 Rem for sure. any action that can take the pressure from those two will most certanly handle the Whisper. If a TC Contender cand handle it any bolt action will.

My Accurate reloading data shows a high of 52,600 PSI. Their load notes say "Maximum average pressures were based on the 221 Fireball which are 52,000 PSI".

Most of their loads are lower that that. The 52,600 PSI load was with a maximum load of 5.5gr of Accurate #2 powder and a 220gr bullet going 889 FPS. #2 is their fasted powder and is similar to Clays etc.

The new Accurate manual has data for a 300 WH/FB? If so, I need one of their new manuals.

You can get their data for free on their website- www.accuratepowder.com

Their 300 Whisper data had been out for at least 5 years.

My manual is at least 8 years old.