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Gunplummer · March 30, 2012, 07:57 AM

Have to agree with that. The crusher method was not all that accurate. The difference lies in the chamber specs. Anybody that worked on guns in the military knew that for years. It is a recent "Discovery" that the military chambers and brass have different specs than SAAMI. Note the load book separations in recent years. It is possible to to have a military rifle with a chamber in spec but on the high limits and load a cartridge on the SAAMI low specs and have a dangerous situation. The body diameter on SAAMI spec ammunition has an average tolerance of .008 and that is a lot. The only time pressure becomes a factor is when the brass is thick and chokes the bullet at the neck. The fact that some military brass is tight in SAAMI chambers should have been an indication that the specs are different. How do you make the brass thicker with out making the neck diameter larger?

March 30, 2012, 07:57 AM	#11
Gunplummer Senior Member Join Date: March 11, 2010 Location: South East Pa. Posts: 3,364	Have to agree with that. The crusher method was not all that accurate. The difference lies in the chamber specs. Anybody that worked on guns in the military knew that for years. It is a recent "Discovery" that the military chambers and brass have different specs than SAAMI. Note the load book separations in recent years. It is possible to to have a military rifle with a chamber in spec but on the high limits and load a cartridge on the SAAMI low specs and have a dangerous situation. The body diameter on SAAMI spec ammunition has an average tolerance of .008 and that is a lot. The only time pressure becomes a factor is when the brass is thick and chokes the bullet at the neck. The fact that some military brass is tight in SAAMI chambers should have been an indication that the specs are different. How do you make the brass thicker with out making the neck diameter larger?