Character being pushed by invisible force

Going from the little information, I am guessing your grenade launcher is not being attached to your character correctly, likely causing a fight between the character and the grenade launcher in that they are overlapping (colliding) and the character is trying to push itself out. That’s why it only happens when you walk, since that’s when it realizes that something is stuck in it.

You should probably look in how you have attached the grenade launcher.

ok so when ever i equip this grenade launcher i made my character is pushed to the left or the right by some invisible force but only when i walk forward… i tried turning off character can step on on all the things connected to my grenade launcher… im using impulse and radial force for projectile