Whilst accepting that some modern firearms (real ones) contain " composite materials", it is still not too unreasonable to expect most guns to be of metallic construction. At our level at least, it conveys an impression of solidity & reality. Air and CO2 arms have no need for plastic.

It may be put across as technology, but again, at our level, I think most of us appreciate engineering.

It may (or may not) shoot right, but if it doesn't feel right, it aint right.

Haven't seen any plastic target pistols or rifles recently.