3 Nm. I am looking at the manual updated as of 10/16 that came with my rifle in December 2017. Now for inch pounds that is 26.5
Now here is another issue. The online 455 manual that I came across says 6 nm for stock screws and 5 nm for barrel screws! Here is the quote from online from 2014
2 Unscrew both stock screws, take off the trigger guard together with the trigger guard plate and then take off the stock. When you
assemble the rifle after you have changed the barrel the stock screws must be tightened at a torque of 6 Nm
5. Loosen both barrel screws and take off the barrel. When you assemble the barrel back again you have to tighten the screws at a
torque of 5 Nm. Always tighten the barrel screws only after you have tightened the magazine housing screws.
(5 Nm is the same in the 2016 version)
Also, the 2016 version gives a torque for the magazine housing screw of 0.8 Nm, the online version does not give any torque specification for the magazine screw.
I plan to alert the CZ-USA folks of the discrepency. If the 2016 book is correct then they should replace the pdf on the web.
http://cz-usa.com/hammer/wp-content/uploads/2014/04/Instruction-Manual-CZ-455.pdf
