I'm not sure I can find a work of great scientific significance that discusses the recoil of crossbows. The best I can come up with is a shop that sells crossbows
http://www.thecrossbowshop.com/index...d=19&Itemid=50
(which admittedly has like 2 lines on it) plus a bunch of examples of scopes being marketed as built to withstand reverse recoil and many of those mention "like what crossbows have", but some don't. I'm not sure why you keep arguing - much like bows, as a crossbow fires most parts move forward - the only force pushing back is the bolt and that's way too light to make a difference, let alone recoil the whole structure back (as opposed to guns where the explosion of the shell pushes the barrel back).

Anyways, if Stanley is medium then Parson is definitely large, which means all the standard weapons look one size category smaller to him than the people they were made for.