I have a 70's era Stoeger Uplander 16ga. I absolutely love the gun, I'll post some pictures when I get home from work. One thing I've noticed recently is that when it gets warm it becomes harder open. When it's cold, it opens like it should, no problems at all. Does anyone know what may be causing this? and possibly a cure? I've cleaned everything and made sure it mates together well and from what I can see everything looks good. Any help here would be greatly appreciated. Thanks!