Baikal RIFLES:
Here's some information that may help you. Baikal is made in Russia. Their web site is (SEE THE LINK BELOW) the guns are imported through Pyramyd air inc and Compasseco inc. You could try both of them to see if they can locate parts for you.
OR: you can search the web for airgun repair and locate someone near you to repair the rifle.
http://www.trulockchokes.com/cgi-bin/eShop/index.cgi
IZ shotguns, also the Baikal brand use the TruChoke system sold also by
Colonial Arms.
This is the same choke style used by the Remington Spartan line
while Remington owned the rights to the Baikal design.
Need the name of the maker to answer.
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Fluss Stahl is Fluid Steel, produced by Krupp, in Essen Germany. But we still need the make of the gun to answer your question.
you can adjust the vent on the MP 153 using a spanner socket.
Check with EAA Corp. European American Armory is the importer for Baikal.