It is a fact that the only people that consider Chokes for barrels on a daily basis are the shotgun fraternity, but Air Rifles are choked depending on the manufacturer.
As in the previous post Chokes are screwed into the end of shotgun barrels the decrease the diameter of the barrel - that forces the loose shot to exit the barrel in a tighter group.
Some Air Rifle manufacturers (Weihrauch were one of the first to do it) crimp the end of their barrels which means in the last inch or so the pellets has to pass through a tighter space. That being the case, any pellets that have become reduced in diameter through friction will be 'sized' and will all exit the barrel exactly the same size, thus offering better accuracy and performance from the rifle.
Many years ago before Carbine rifles became available it wasn't unusual to come across a shooters that had cut down their barrel to create a shorter rifle only to find they now couldn't hit a bl**dy thing !
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