dimensions ?

[uglyarms]

I would appreciate the dimensions of the barrel tennen of a barrel that screws into a FN SPR action including the degree ( angle ) of the cone . A pre 64 model 70 barrel lacked about 3/4 of a turn of seating to the action . The lack of threads at the back of the action has me a little (lot) befuddled !? Thanks for any help you can offer .
Tim

 

[wapiti25]

You need to be very specific as to which FN action you are talking about as they have made several.