Some writers have the opposite problem, however – they write, write and write until their tome is well beyond the usually accepted 100,000 words. There’s nothing wrong with this – a good number of debut novels have exceeded this word-count. But you’re bucking against the standard requirement of publishers and agents by writing such a thick novel, thereby lessening your chance of acceptance.
If you see your book growing to huge proportions, then you might like to take a look at this blog I posted in 2014:
My book Write a Western in 30 Days has picked up a good selection of reviews, and many of the reviewers on Amazon sites state that it's useful for writers of any genre, not only westerns.