A friend of mine brought me a .40 baby desert eagle. He had disassembled it and had not been able to reassemble it. I found the problem to be a stuck safety pin. With the safety set to fire I was able to pop it back in but it was stiff. I worked the safety on and off a few times and it restuck. After unsticking it again I was unable to make it jam again. My friend admits to hosing the gun down with wd40. My question is does this need to go to a gunshop or will a thorough delubing and relubing with a proper gun oil solve the problem?