03a3 Max pressure

[EO1]

Does anyone know the official spec for maximum working pressure of a Rem (or SC) made 1903/1903a3 ?

[PhillipM]

50,000 psi working. Proof load was 70,000... That may have been raised to 75,000.

[EO1]

Do you have a reference source for that ?

[PhillipM]

Hatcher's Norebook. Standard M2 ball spec is 50,000 regardless of rifle or machinegun. The 03A3 was built to fire that ammunition. The 70,000 psi load is called a blue pill. For the rifles to be accepted, this round had to be fired, earning the rifle it's P proof mark.

[EO1]

Thankee.

[raymeketa]

The specified pressure of both the standard service ammunition and the high pressure test cartridges can be found in any number of places such as TMs and FMs. SAAMI also has their own Service Max and Proof Cartridge Max specs. The numbers can vary but 50,000 and 75,000 psi are considered nominal.

Max pressures for the 03A3 rifles themselves is another thing altogether. You'd have to find official documents that give this information. Contemporary reports seem to indicate that 75000 psi was at or near the upper limit. OTOH, tests of the Garand documented pressures well over 100,000 before things began to go bad. Testing rifles to destruction is not something that manufacturers like to do because what destroys the rifle will also destroy the test equipment.

[Parashooter]

In modern terms, that's 50000 C.U.P. (Copper Units of Pressure) maximum average pressure (MAP), as determined in by the old standby copper crusher type gauge. This method has now been largely superseded by the piezo transducer system, which can give a more precise reading of peak pressure. With the transducer method, MAP for the .30/06 cartridge is 60000 psi - same actual pressure but different units. Many old references gave crusher figures as "psi" but that usage has been outdated for many years. The two systems and units have become a source of much confusion to those with limited exposure to internal ballistics. This text and table from a 1987 Hercules data guide may help clarify the difference -

[chuckindenver]

proof test,,,125,000 blue pill

[raymeketa]

Is that a test for the barrel only?

[chuckindenver]

receiver, and barrel together... keep in mind thats max pressure,, not what the proofed all rifles at.
like the other posts.. 50 to 75,000 was average pressure