How to Weld a Mesh To Another Animated Mesh

Well its not animation per gun. I already have it so that each gun has unique animation sets. Instead this post is about animation per attachments…

if I had 20 guns, 10 red dot sights then thats 200 animations. That is not reasonable. And thats only optic attachments not considering other attachments like grips, underbarrel, rails, flashlights.

Not feasible. Thats why solo devs opt for the procedural approach- the method im using.