I don't know if this will work for you, but this is the first object I ever skinned:



What I did was I made a side view skin in MED. Opened it in photoshop. Then I took the picture of the gun, set it as a new layer with 60% opacity so I could see the wireframe underneath. I stretched it to fit the wireframe. Then i made a copy of the layer and put it on the other side of the gun, and scaled it to fit the wireframe of the otherside. I did some cloning to get rid of some of the switches and stuff on the appropriate sides. Then I brought the opacity of the two layers back to 100, flattened the image and saved it as a bmp. I imported it into MED, made small edits to the skin vertices to get a better fit and then I was done. Voila Walther P38. It works well for guns at the least, maybe you can adopt this procedure for other models.