The word 射 vs the word 短
射 was originally written 䠶, that is a body and an arrow, giving the meaning shooting. But 身 is here a phonetic component, which just happens to also have a symbolic sense. 寸 is just how the original 矢 has been distorted in writing.

短 is actually an arrow 矢 shot into a 豆, which is not a bean but some sort of vessel. Why it means short is unknown, but we can note that another word for short, 矮, also contains 矢.