nearly con^ant, or, being only slightly retarded, unless 

 there Is a great deformation of the shot In passing into 

 the choke, so that the front portion of the charge is 

 accelerated whilst the rear portion is retarded as compared 

 with the mean velocity of the charge, the extremes being 

 + about A% ; thus the charge of shot on leaving the 

 muzzle is no longer in a compad mass, the front portion 

 tending by virtue of its higher velocity to get further and 

 further in front of the rest of the charge, whilst the rear 

 portion tends to lag more and more behind, and the shot 

 is no longer pressed tightly together nor against the sides 

 of the barrel. The tendency of the front pellets to separate 

 from those behind them is, however, kept in check by the 

 wad in front, which is greatly retarded by the pressure of 

 air on its front surface. In the majority of cases the front 

 wad is soon displaced laterally, so that the charge can 

 proceed unimpeded. In the same way the recur wad is 

 forced up against the rear pellets, which have been retarded 

 by the adlion of the choke, so that they regain some of the 

 velocity which they have lost ; but in the meantime the 

 bulk of the pellets have escaped from the barrel free from 

 the disturbing Influences of the front and rear wads. The 

 a<flion may therefore be summarised as follows : 



On passing through the choke an advance guard Is 

 thrown forward, which takes charge of the front wad and 

 defleds it out of the line of march of the main body, 

 whilst a rear guard is left behind which wards off the 

 attacks of the felt and over powder wads, the result being 

 that better order is kept and there are fewer stragglers. 



The occasional lower velocity in the choke barrel may 

 be due to the jamming of the shot in the choke when they 



52 



