Different bones position depending on animation

Hello there,
I’m currently working on a project and i’ve a problem with my character animations and my guns.
My character has a lot of animations attached to him (Like walk, run, jump), each animations has two states :
One without anything in hands, and the other one with guns, grenade, melee weapons, and so on.

I don’t have problem with my animation, however the problem is when my character grab a gun in the idle position for exemple, the weapon is automaticaly attached to a socket in the right hand. The socket has a specific transform, and in this position, everything is great. But, when my character walks, the socket doesn’t fit anymore. My first idea was to create a socket for each animation, but… If I have 25 animations, it will be a matter ahah

If you guys have a solution, I’ll take it !
Thx for all guys !