Home Forums Reloading Big Game Rifles Cratered and Pierced Primers - Advice Needed

RiverRider

The secret to understanding .223/5.56 chamber pressures is to remember your an American and our speed limit signs are in MPH and not KPH. Meaning it doesn't matter how Europe measures chamber pressure we Americans use two methods. The copper crusher method (CUP) or copper units pressure or the transducer method that measures pressure in PSI or pounds per square inch.

Below is the milspec standard for commercial ammunition made for the military. At 3.7 the chamber pressure is listed as 55,000 psi SAAMI transducer method.



Now look below at the .223 with the SAAMI and CIP standards.

Cartridge Pressure Standards
http://kwk.us/pressures.html

Bottom line American 52,000 cup, 55,000 psi and European 62,000 psi are all three the same pressure measured three diffrent ways. Or back to the speed limit signs 60 mph = 100 kph are both the same speed.

And below from the Army TM 43-0001-27