The Shot- Gun. 779 



This stamp is that used by the V & \tJ3fL 

 Guardians of the Birmingham Proof- V^S 1 v^S'wm NOT F0R BALL 

 house: f ^ /°3& 



An examination of the table shows that the charge of powder 

 used in provisional proof is about 2>Vi times the average field 

 charge, and in definitive proof it is about 2)4, times the field 

 charge. The ball, or charge of shot, has very little more weight 

 than the average charge used by the sportsman. 



Belgium is the only country, besides England, whose laws require 

 the proving of gun -barrels. At the Liege proof-house, each breech- 

 loader is proved thrice. First, the barrels are tested, then the barrels 

 and breech-action, and finally the finished gun. The proof charges 

 for a twelve-gauge gun are a bullet, or a charge of shot weighing 

 34 grammes. Twenty-two grammes of powder are used in the 

 first proof, 15 grammes in the second, and 7 grammes in the 

 third proof. ^ 



The following are the Belgium proof-marks : ^ &> # 



To Test the Straightness of the Bore of a Gun-barrel. — 

 The barrels of high-priced guns are not always straight. They 

 may have been so before they were soldered together and ribbed, 

 but these operations often draw and bend the barrels. The straight- 

 ness of a barrel can be readily tested by any purchaser in the 

 following manner: Take a thin card -board wad of the gauge of 

 the gun, and with a pair of dividers get its center. Perforate 

 this center with a pinhole. Place the muzzle of the gun on the 

 floor, and push the wad from the breech till it reaches the floor at 

 the muzzle-end of the gun. Now point the barrel toward the bright 

 sky or at the porcelain shade of a lamp. Place the breech of the 

 barrel quite close to the eye and look at the brightly illuminated 

 pinhole. You will see this hole in the axis of the barrel. Around 

 it, as a center, you will observe three or four bright rings. If the 

 barrel be straight these rings will be perfectly concentric, with the 

 pinnole for their common center. If the barrel be bent, say to the 

 left, then the circles will appear as, if slid to the left of the central 

 pinhole ; the direction in which the circles appear displaced cor- 

 responds to the direction in which the barrel is bent. 



The above is a severe test, and there are few barrels that will 

 stand it. A similar test, though less searching, may be applied by 

 merely placing the breech very close to the eye and looking through 



