GUNS AND AMMUNITION. 



*33 



DRIFT OF PROJECTILES. 



G. P. SERVLV 



Dr. YVyk Wager says he does not believe 

 a rifle bullet drifts, simply because he does 

 not understand why it should. I suppose he 

 will be greatly surprised to learn that the 

 drift of all kinds of projectiles fired from 

 rifled barrels is not a matter of opinion but 

 an established fact. The drift of different 

 guns, on known ranges, has been accu- 

 rately measured. For instance, the drift of 



air is also increased on the under side. The 

 under side of the bullet is moving to the left, 

 and thus the bullet tends to roll to the right 

 on the cushion of air formed under it. 

 This explanation applies equally to a bul- 

 let fired at an angle of elevation, the axis of 

 rotation always remaining at this angle 

 while the bullet traces its parabolic curve, 

 thus increasing the air pressure on one of 

 the moving faces of the bullet and produc- 

 ing the drift. 



I should like to hear from any reader of 



the bullet from a Springfield rifle on a 

 range of 1,000 yards is 43 inches to the 

 right. 



I have never seen a reason given as to why 

 a bullet drifts; but it is evidently a simple 

 one. A projectile fired horizontally, and 

 rotating to the right, begins to drop as 

 soon as it leaves the gun. This is owing to 



Recreation who uses a .22 calibre No. 4 

 Remington rifle. I consider mine better 

 than a Stevens because of its superior action 

 in extracting the shells, throwing them 

 clear of the gun, which the Stevens does not 

 do. How do the 2 guns compare in ac- 

 curacy? I have never shot a Stevens? 



Garrett P. Servin, Jr. 



the action of gravity. The bullet traces a 

 curve to the ground; but in the mean-time 

 the axis of the bullet has remained hori- 

 zontal because of the twist. The bullet in 

 dropping through the air increases the 

 pressure of air on its under side. The air 

 pressure being increased on the under side 

 of the bullet the friction of the bullet on the 



The accompanying diagram No. 2 repre- 

 sents the course of projectile viewed as fired 

 almost directly aw.;y from the observer. 

 The bullet is shown in 3 positions P, P' and 

 P" and is supposed to be rotating to the 

 right as shown by the arrows at the base of 

 bullet. It will readily be seen that as the 



