No you’re misundertanding. I dont want to paint which vertexes will just disappear, or paint a mask in a DCC and say this disappears, this dosent.
I want to be able to change what disappears based on what scope you have on the gun and its specific position on the gun. You cant just make a mask that works for every scope on every gun.
Which is why the solution I was originally trying to achieve, and what Chosker mentioned would be ideal, because its completely dynamic.