This guy may have the answer to that as I know he sells/sold the bamboo plugs on ebay occasionally:
http://bambooarrows.com/
However, even on his instructional site he advises the use of hard wood for nocking and making a tapered point to glue on ones point.
Greenmanarchery also says this:
While this is a bit of an extreme example you can easily see why the shaft will be easier to work with when the center of the bamboo is filled.
Once the glue is set the ends of the shafts are tapered for the field points on the Woodchuck taper tool. With bamboo you need to use a sanding-type taper tool. The pencil sharpener style of taper tool won't work on bamboo.
So naturally its harder to use bamboo for such a purpose. Traditionally, it was hardwood used for such purposes usually when crafting the Korean bamboo arrow.