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BOOK V. 



THE SPORTING RIFLE. 



CHAPTER I. 



THE THEORY OF RIFLE SHOOTING, AND THE MODE 

 OF RIFLING THE BARREL. 



DEFINITION OF THE RIFLE VELOCITY DIMINISHED BY RIFLING A SMOOTH 

 BORE GREATEST AT THE MOMENT WHEN THE BALL LEAVES THE 

 MUZZLE VARIETIES IN THE FORM OF THE GROOVES ALMOST INFI- 

 NITE THE BARREL METHOD OF RIFLING TECHNICAL TERMS. 



A rifle may be defined to be a species of gun which causes its 

 projectile to rotate around the line of its flight. This is 

 effected by means of spiral grooves or channels, which are 

 cut on its internal surface, sometimes so slightly as to be 

 invisible to the eye, but generally with a sharp margin. The 

 consequence of this form is, as described by Robins, " that 

 when the piece is fired, the indented zone of the bullet follows 

 the sweep of the rifles ; and thereby, besides its progressive 

 motion, acquires a circular motion round the axis of the 

 piece, which circular motion will be continued to the bullet 

 after its separation from the piece; by which means a bullet 

 discharged from a rifled barrel is constantly made to whirl 

 round an axis which is coincident with the line of its flight. 

 And hence it follows, that the resistance of the foremost end 

 of the bullet is equally distributed round the pole of its 

 circular motion, and acts with an equal effect on every side 

 of the line of direction, so that this resistance can produce 

 no deviation from that line. And (which is still of more 

 importance) if, by the casual irregularity of the foremost 



