How to create weapon switch like I have primaey weapon and when i click 1 or 2 button weapon changes to Pistol.
I will create both weapon blueprint weapon but how can I switch between Them!! Help! 
Turn one off and turn one on? Put one in the socket and take the other one out of the socket? Choose your poison.
I think you didn’t understand my question. I am asking how how do I change weapon blueprint (i.e. I have created a primary weapon blueprint which is automatic weapon and another which fire 1 bullet at a time) I want when I click 1 Secondary weapon blueprint activate and when I click 2 Primary weapon blueprint Enables.
That sounds like a Branch situation to me. Not telling you how to build your blueprints, but what I would do is put both the automatic and single-shot (along with whatever other firing methods I think of) into one blueprint and have a Boolean Variable or Enumeration determine which type of firing to do, branching off accordingly.
Hey , glad to see your help 
You must have player call of duty. Player click 1 and gun changes I want to do something like that. (Not different firing modes)
My Progress: Till now I have created a automatic line trace weapon with reload function. Its just been Few weeks weeks with ue4 and I started liking the blueprint system.
My Progress:I have successfully created a automatic rifle with the rich reload system and I have also created a working weapon switch system. Thanks Everyone!
Glad to see you have things running well.