What does "scripture" mean in NT writing? This is slightly a take-off from: 
What does it mean that all scripture is God-Breathed?

The Bible as we know it today wasn't canonized and compiled into a single volume until much later. In particular, I am concerned with the reference to all scripture being "God-breathed" (inspired) in 2 Timothy, as it was written long before (varying, based on which "canonization" we consider) any canonization.

So what was meant/intended by the authors by the term "scripture" at the time of New Testament writings?
The word for "scripture" in the Greek text is (ἡ) γραφή, often occurring in the plural, (τῆς) γραφῆς, which literally means "writing(s)." The word occurs approximately 50 times in the New Testament (depending on the manuscript used it is 50 or 51) and it seems pretty clear to me from a word search that this almost exclusively refers to the Old Testament writings when used by New Testament authors.

The exception is 2 Peter 3:16, which says:


  And regard the patience of our Lord as salvation, just as also our
  dear brother Paul wrote to you, according to the wisdom given to him,
  speaking of these things in all his letters [(ἐπιστολαῖς, epistles)]. 
  Some things in these letters are hard to understand, things the ignorant 
  and unstable twist to their own destruction, as they also do to the rest 
  of the scriptures [(γραφὰς, writings)] (2 Peter 3:15-16, NET).


This verse clearly refers to Paul's writings as "scriptures." Everywhere else it refers to the Old Testament (or to specific passages from the Old Testament).

Even by the earliest dating standard for 2 Peter, all of Paul's epistles that are included in the New Testament would have been written by the time this statement was made with the possible exceptions of 2 Timothy (possibly written the same year as 2 Peter, although most likely before as 2 Peter was probably not written until at least 65 and 2 Timothy was almost certainly written in 64) and Hebrews (whose author is disputed anyways). 2 Peter is also considered to be antilegomena, although it has been widely accepted by the Church throughout history.

It is thus my opinion that St. Paul was not referring to New Testament writings when he said that all scripture is God-breathed (2 Timothy 3:16), but rather to Old Testament writings.