RIFLE-BARREL STEEL, .30 CALIBER.
70
No. 7400.
Marks, M 3 D.
Sectional area, .25 square inch. Gauged length, 1".
Specimen from the bar.
.Remarks.
Initial load.
Elastic limit.
Tensile strength.
Permanent set.	Successive permanent set.
Inch. 0.	Inch. 0.
	
	
	
	
	
1	
		
		
	
	
	
	
	
	
	.
	
		
	
Successive elongation per inch.
Inch.
0.
.0001 . 0003 .0003 .0003 .0003 . 0005 .0002 . 0002 .0103 .0011 .0007 . 0017 .0040 .0045 .005 .01 .02 .04
Elongation per inch.
Inch.
0.
.0001 .0004 .0007 .0010 .0013 .0018 . 0020 . 0022 . 0125 .0136 . 0143 .0160 .0200 .0245 .03 .04 .06 .10
Applied loads per square inch.
Pounds. 1,000 5,000 10,000 20.000
30.000
40.000
50.000
58.000
59.000
60.000 61,000 62,000
64.000
68.000
72.000
76.000
80.000 88,000 96,000 97,600
General summary.
.....................pounds.. 97,600
......׳................do.... 59,000
.......................inch..	.20
.......................do.......0022
granular 50 per cent, silky 50 per cent
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............... .......