I have a Small Arms Industries silencer among a collection of bits I bought.It weighs 77 grams,is 25mm diameter by 62mm long and has an 8mm bore with a 1/2 female UNF fitting.It appears to have 2 chambers with washers and springs that move fitted.It's tiny.It does actually work quite well on a Co2 pistol.I can't find another and wondered what it was originally intended for.
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