You need to know the make, grade and model. 270 mag rifle could be anything
What is the value of a Remington 700 bolt action 270ml rifle?
1951
100-400 USD
500-1000 USD
You will have to call FN to find out.
IIRC, Winchester.
65.00
They did make .270 barrels for conversions of other firearms, but I'm unable to find any references to them ever manufacturing a bolt action .270.
AFAIK they never made a bolt action shotgun
100-1000 depending on specifics
10-350 USD, no.
0-500 uSD