The grade won't be 'capped', it just won't be enough to achieve a good one. You lot have some strange opinions on what goes into marking.
A marker is not gonna look at it, see the wordcount, and say 'well, that's capped at 50' (which is what 'capping' actually means). They will mark it as normal and it will very likely be a poor piece of work in virtue of its being too short to treat the subject matter with the gravitas required. The mark will reflect the quality, not a 'cap'.
Also - it's not always the case the references are excluded. In a piece this short, probably. But sometimes they are not (where I work includes the refs in their wordcounts), so do not take this for granted. Read and re-read the questionsheet/spec sheet. Know what is expected of you, and if you don't, seek help early on.