Boy Scout – Ring of Force Shield with Archery

I am curious if there is a clarification of the rules, which is about a ring of force shield with archery. I know people will say you can disable the ring, make a full attack, and activate the ring in the same turn

This somehow seems wrong and may be an example of using RAW to defeat RAI. For one thing, how long is the shield open during the round? I think it goes against the common sense that I can only attack when the shield is up, no matter how short it is