Back-bored Beretta bothers
QI mostly shoot clays at local shoots, and the vast majority of the places are fibre-wad only. I shoot a Beretta which is back-bored to reduce recoil, but a friend of mine said that back-bored barrels don’t work with fibre wad shells. Is that right?
ADON BRUNT replies: Your friend is right to an extent. Back-bored barrels are a little wider in diameter than barrels which use standard profiles. The issue is the gas seal in the barrels as the cartridge is fired.
A plastic wad is flexible and as such it will spread out to produce a tight seal with the barrel walls when under pressure. On the other hand, a fibre wad doesn’t have as much ‘give’ in it so won’t distort enough to produce a perfect seal. Without a tight seal, some of the pressure generated by the powder is lost and with that loss of pressure there is a corresponding loss of energy imparted to the shot column, which translates into a reduced velocity and arguably a degree of inconsistency in performance.
Chances are you will have adapted to the performance of your gun/cartridge combination so I wouldn’t panic too much. However, if you intend to mostly shoot fibres in the future, I would consider a gun with tighter tubes if you do change your gun at some point.