Making model, ingame textures are messed

[Scoliosis]

k i was messing around with model injection to see how it works. I downloaded another weapon from another game resized it and converted it to wavefront obj. It also had a texture (which btw looked PERFECT in milkshape) I imported the texture as well as a seperate dds on the map i was testing injection on (coagulation) when i started the game the texture were completely wrong. Like they were all messed. They didnt line up with the gun. how do I fix this?