BSA Barrel Extension - 40mm (55mm) - Steel
BSA barrel extension which is useful if you have a Tench/HuMa regulator, pressure gauge or extended air cylinder fitted to your rifle and you can't fit your moderator without it fouling on the air cylinder.
It has roughly a 14mm long 1/2" UNF male thread on one side and roughly a 16mm deep 1/2" UNF female thread in the other.
It is around 54mm over all, with around 40mm being the same diameter as the barrel (15.5mm).
They are made of high quality steel, they are blued to match your barrel. I also sell an un-blued version which costs a little less.
They are not calibre specific and they don't have any internal rifling.
They weigh approximately 45 grams