RIFLE־BARREL STEEL, .30 CALIBER,
76
No. 7397.
Marks, M 3 C.
Sectional area, .25 square inch. Gauged length, 1".
From butt of finished barrel.
Rolled, and cooled in the air.
Applied loads per square ipch.	Elongation per inch.	Successive elongation per inch.	Permanent set.	Successive permanent set.	.Remarks.
Pounds. 1,000 5,000	Inch. 0. . 0002 .0004 .0006 .0009 .0013 .0016 .0019 .0160 .0170 .0176 . 0182 .0205 . 0230 .03 .04 .05 .09	Inch. 0.	Inch. 0.	Inch. 0.	Initial load.
					
20,000 30.000 40.000 50.000 56.000 57.000 58.000		.0002			
					
					
		.0003 .0003			
					Elastic limit.
					
		.0010 .0006 .0006 .0023 .0025 007			
					
60,000 62,000					
					
					
68,000 72,000					
			*		
		.01 .04			
88,000 92,480					
					Tensile strength.
					
..pounds.. 92,480
.....do... 56,000
....inch.. .80
.....do... .0019
silky, cup-shaped
General summary. *
Tensile strength per square inch of original section....
Elastic limit per square inch of original section.......
Elongation per inch after rupture.......................
Elongation per inch under strain at elastic limit.......
Character of broken surface.............................